Electroactive anticorrosion coatings are specialized surface treatments that prevent or minimize corrosion. Thestudy employs strategic thermodynamic equilibriumcalculations to pioneer a novel factor in corrosion prote...Electroactive anticorrosion coatings are specialized surface treatments that prevent or minimize corrosion. Thestudy employs strategic thermodynamic equilibriumcalculations to pioneer a novel factor in corrosion protection.A first-time proposal, the total acidity (TA) potential of the hydrogen (pH) concept significantly shapes medicalmagnesium alloys. These coatings are meticulously designed for robust corrosion resistance, blending theoreticalinsights and practical applications to enhance our grasp of corrosion prevention mechanisms and establisha systematic approach to coating design. The groundbreaking significance of this study lies in its innovativeintegration of the TA/pH concept,which encompasses the TA/pH ratio of the chemical environment. This approachsurpasses convention by acknowledging the intricate interplay between the acidity and pH levels within thecoating formulation, thereby optimizing metal-phosphate-based conversion coatings and transforming corrosionmitigation strategies. To authenticate the TA/pH concept, the study comprehensively compares its findings withexisting research, rigorously validating the theoretical framework and reinforcing the correlates among TA/pHvalues and observed corrosion resistance in the coatings. The influence of mutations that occur naturally inthe detergent solution on persistent phosphorus changes is shown by empirical confirmation, which improvescorrosion resistance. This realization advances the field ofmaterials and the field’s knowledge of coated generation,particularly anticorrosion converter layers.展开更多
Electromagnetic wave(EMW)absorbing materials have an irreplaceable position in the field of military stealth as well as in the field of electromagnetic pollution control.And in order to cope with the complex electroma...Electromagnetic wave(EMW)absorbing materials have an irreplaceable position in the field of military stealth as well as in the field of electromagnetic pollution control.And in order to cope with the complex electromagnetic environment,the design of multifunctional and multiband high efficiency EMW absorbers remains a tremendous challenge.In this work,we designed a three-dimensional porous structure via the salt melt synthesis strategy to optimize the impedance matching of the absorber.Also,through interfacial engineering,a molybdenum carbide transition layer was introduced between the molybdenum selenide nanoparticles and the three-dimensional porous carbon matrix to improve the absorption behavior of the absorber.The analysis indicates that the number and components of the heterogeneous interfaces have a significant impact on the EMW absorption performance of the absorber due to mechanisms such as interfacial polarization and conduction loss introduced by interfacial engineering.Wherein,the prepared MoSe_(2)/MoC/PNC composites showed excellent EMW absorption performance in C,X,and Ku bands,especially exhibiting a reflection loss of−59.09 dB and an effective absorption bandwidth of 6.96 GHz at 1.9 mm.The coordination between structure and components endows the absorber with strong absorption,broad bandwidth,thin thickness,and multi-frequency absorption characteristics.Remarkably,it can effectively reinforce the marine anticorrosion property of the epoxy resin coating on Q235 steel substrate.This study contributes to a deeper understanding of the relationship between interfacial engineering and the performance of EMW absorbers,and provides a reference for the design of multifunctional,multiband EMW absorption materials.展开更多
The stimuli-responsive anticorrosion coatings have drawn great attention as a prospective corrosion protection approach due to their smart self-repairing properties.In contrast to passive protection mechanism based on...The stimuli-responsive anticorrosion coatings have drawn great attention as a prospective corrosion protection approach due to their smart self-repairing properties.In contrast to passive protection mechanism based on post-corrosion microenvironmental changes,a unique active protection strategy based on nanocatalytic oxygen depletion is proposed in this work to inhibit the occurrence of corrosion.Porous FeeNeC catalysts with outstanding oxygen reduction reaction(ORR)activity(half-wave potential of 0.89 V)is firstly synthesized through pre-coordination with organosilane precursor to obtain homogeneously distributed active sites.When this catalyst is introduced into the coating matrix,uniformly distributed FeeNeC not only compensates the defects but plays a crucial role in adsorption and consumption of diffused oxygen in the coating.Under this dual action,the penetration of corrosive medium,especially oxygen,through coating to metal substrate is greatly suppressed,resulting in effective corrosion inhibition and a significant increase in corrosion resistance of the composite coating compared to pure epoxy coating.This work provides a new perspective and the starting point for the design of high-performance smart coating with active anticorrosion properties.展开更多
There is a great challenge to fabricate superhydrophobic coating with excellent mechanical durability and corrosion resistance.Inspired by the pinecone-shaped structure,a novel reduced-graphene oxide(rGO)/Ni composite...There is a great challenge to fabricate superhydrophobic coating with excellent mechanical durability and corrosion resistance.Inspired by the pinecone-shaped structure,a novel reduced-graphene oxide(rGO)/Ni composite coating with pinecone-like micro/nanostructures was fabricated successfully on a stainless steel substrate using a simple electrodeposition method combining Ni pre-deposition and an elevated current assistant approach.The results show that the coating is of self-cleaning and superhydrophicity with a water contact angle(CA)of 162.7°±0.8°and a sliding angle(SA)of 2.5°±1.0°.Importantly,the coating still maintains the excellent self-cleaning and superhydrophicity,water CA of 155.8°±1.2°and SA of 5.9°±1.2°,even after 100-cycle mechanical abrasion.Meanwhile,the coating also exhibits good anticorrosion performance in 3.5 wt%NaCl solution,with 99.98%inhibition efficiency.The simple fabrication method may provide a cost-effective way to prepare mechanically durable,anticorrosive,self-cleaning and superhydrophobic coatings on metal substrates.展开更多
Corrosion of reinforced concrete structures is a serious problem in ocean engineering. As an orientation of study, anticorrosion coating technique is developed and widely applied, but many problems need to be solved. ...Corrosion of reinforced concrete structures is a serious problem in ocean engineering. As an orientation of study, anticorrosion coating technique is developed and widely applied, but many problems need to be solved. LSW-2 type anticorrosion coating for maritime reinforced concrete structures is characterized by sea water resistance, salt fog resistance, moisture and heal resistance as well as impermeability to chlorions. The new type coating can be applied to wet concrete surface by conventional construction technique. It is a breakthrough in solving the above mentioned problem. The paper mainly introduces the test results, the property indices, coating procedure, construction technique and economic benefit of Ihe coating.展开更多
Epoxy resin powder coating has been successfully applied on the corrosion protection of magnesium lithium alloys.However,poor wear resistance and microcracks formed during the solidification have limited it extensive ...Epoxy resin powder coating has been successfully applied on the corrosion protection of magnesium lithium alloys.However,poor wear resistance and microcracks formed during the solidification have limited it extensive application.There are limited approaches to exploit such anti-corrosion and mechanical properties of magnesium lithium alloys.Herein,the epoxy resin powder coating with polydopamine modified molybdenum disulfide(MoS_(2)@PDA-EP powder coating with 0,0.1,0.2,0.5,1.0 wt.%loading)was well prepared by melt extrusion to investigate its anticorrosion performance and wear resistance.The results revealed that the addition of MoS_(2)@PDA enhanced the adhesion strength between coatings and alloys,wear resistance and corrosion protection of the powder coatings.Among them,the optimum was obtained by 0.2 wt.%MoS_(2)@PDA-EP powder coating which could be attributed to well dispersion and efficient adhesion with coating matrix.To conclude,MoS_(2)@PDA-EP powder coating is meaningfully beneficial for the anticorrosive and wear performance improvement of magnesium lithium alloys.展开更多
A new surface protection process was developed to magnesium alloy against corrosion in aggressive environments.Firstly,a phosphate coating was formed on rinsed magnesium alloy.Then,powder painting was carried out on t...A new surface protection process was developed to magnesium alloy against corrosion in aggressive environments.Firstly,a phosphate coating was formed on rinsed magnesium alloy.Then,powder painting was carried out on the phosphated magnesium alloy.Surface morphologies and phase compositions of the phosphate coating were investigated by X-ray diffraction(XRD) and scanning electron microscope(SEM) .The results show that the phosphate coatings formed in bath containing earth additives at room temperature have dense and fine microstructure.The phosphate coating provides excellent paint adhesion to the magnesium alloy. Salt spray tests indicate that the corrosion resistance of the phosphate coating plus paint could meet the demand of magnesium alloy automobile components in aggressive environments.展开更多
In order to investigate the anticorrosion performance of the organic coating/metal system, electrochemical impedance spectra (EIS) were measured in the 3.5wt% NaCl solution, the chemical component and the formation ...In order to investigate the anticorrosion performance of the organic coating/metal system, electrochemical impedance spectra (EIS) were measured in the 3.5wt% NaCl solution, the chemical component and the formation of corrosion products scale were analyzed by laser Raman microspectroscopy, and the pattern of the organic coating/metal system was observed by scanning electron microscopy (SEM). The characteristics and the delamination process of the organic coating/metal system were investigated systematically, and the emphases were on the transportation of the corrosive medium and the changes of the coating/metal interface. The results show that the impedance decreases at the initial immersion, then increases at the middle-immersion, and again decreases at last, which is related to the corrosion products scale. The concentration of Cl in the coating, which destroys the corrosion products scale, increases with the immersion time.展开更多
Smart coating for corrosion protection of metal materials(steel,magnesium,aluminum and their alloys)has drawn great attention because of their capacity to prevent crack propagation in the protective coating by releasi...Smart coating for corrosion protection of metal materials(steel,magnesium,aluminum and their alloys)has drawn great attention because of their capacity to prevent crack propagation in the protective coating by releasing functional molecules(healing agents or corrosion inhibitors)on demand from delivery vehicle,that is,micro/nanocontainer made up of a shell and core material or a coating layer,in a controllable manner.Herein,we summarize the recent achievements during the last 10 years in the field of the micro/nanocontainer with different types of stimuli-responsive properties,i.e.,pH,electrochemical potential,redox,aggressive corrosive ions,heat,light,magnetic field,and mechanical impact,for smart anticorrosion coating.The state-of-the-art design and fabrication of micro/nanocontainer are emphasized with detailed examples.展开更多
The aim of this study was to develop a method to prepare WO<sub><span style="font-family:Verdana;">3</span></sub><span style="font-family:Verdana;">-TiO</span>&l...The aim of this study was to develop a method to prepare WO<sub><span style="font-family:Verdana;">3</span></sub><span style="font-family:Verdana;">-TiO</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;"> film which has high anticorrosion property when it was coated on type 304 stainless steel. A series of WO</span><sub><span style="font-family:Verdana;">3</span></sub><span style="font-family:Verdana;">-modified TiO</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;"> sols were synthesized by peroxo-sol gel method using TiCl</span><sub><span style="font-family:Verdana;">4</span></sub><span style="font-family:Verdana;"> and Na</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;">WO</span><sub><span style="font-family:Verdana;">4</span></sub><span style="font-family:Verdana;"> as the starting materials. TiCl</span><sub><span style="font-family:Verdana;">4</span></sub><span style="font-family:Verdana;"> was converted to Ti(OH)</span><sub><span style="font-family:Verdana;">4</span></sub><span style="font-family:Verdana;"> gel. H</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;">O</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;"> and Na</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;">WO</span><sub><span style="font-family:Verdana;">4</span></sub><span style="font-family:Verdana;"> were added in Ti(OH)</span><sub><span style="font-family:Verdana;">4</span></sub><span style="font-family:Verdana;"> solution and heated at 95<span style="white-space:normal;">°</span>C. The WO</span><sub><span style="font-family:Verdana;">3</span></sub><span style="font-family:Verdana;">-TiO</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;"> sol was transparent, in neutral (pH^7) solution, stable suspension without surfactant, nano-crystallite and no annealing is needed after coating, and very stable for 2 years in stock. WO</span><sub><span style="font-family:Verdana;">3</span></sub><span style="font-family:Verdana;">-TiO</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;"> sol was formed with anatase crystalline structure. These sols were characterized by XRD, TEM, and XPS. The sol was used to coat on stainless steel 304 by dip-coating. The WO</span><sub><span style="font-family:Verdana;">3</span></sub><span style="font-family:Verdana;">-TiO</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;"> was anatase in structure as characterized by X-ray diffraction. There were no WO</span><sub><span style="font-family:Verdana;">3</span></sub><span style="font-family:Verdana;"> XRD peaks in the WO</span><sub><span style="font-family:Verdana;">3</span></sub><span style="font-family:Verdana;">-TiO</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;"> sols, indicating that WO</span><sub><span style="font-family:Verdana;">3</span></sub><span style="font-family:Verdana;"> particles were very small, possibly incorporating into TiO</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;"> structure, providing the amount of WO</span><sub><span style="font-family:Verdana;">3</span></sub><span style="font-family:Verdana;"> was very small. The TiO</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;"> particles were rhombus shape. WO</span><sub><span style="font-family:Verdana;">3</span></sub><span style="font-family:Verdana;">-TiO</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;"> had smaller size area than pure TiO</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;">. The SEM results showed that the film coated on the glass substrate was very uniform. All films were nonporous and dense films. Its hardness reached 2 H after drying at 100<span style="white-space:normal;">°</span>C, and reached 5 H after annealing at 400<span style="white-space:normal;">°</span>C. The WO</span><sub><span style="font-family:Verdana;">3</span></sub><span style="font-family:Verdana;">-TiO</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;"> film coated on 304 stainless steel had better anticorrosion capability than the unmodified TiO</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;"> film under UV light illumination. The optimum weight ratio of TiO</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;">: WO</span><sub><span style="font-family:Verdana;">3</span></sub><span style="font-family:Verdana;"> was 100:4.</span>展开更多
Simulated adsorptive experiments using the axletree and lubricating oil containing anticorrosion additive were conducted,and the UV absorbance of the lubricating oil before and after the adsorptive experiments was mea...Simulated adsorptive experiments using the axletree and lubricating oil containing anticorrosion additive were conducted,and the UV absorbance of the lubricating oil before and after the adsorptive experiments was measured.Through the UV spectral measurements the difference in UV absorbance of the lubricating oil before and after the adsorptive experiments was identified,the adsorbed quantity of anticorrosion additive in the interfacial film between lubricating oil and bearing was calculated using the Lambert-Bell principle to verify the adsorption of corrosion inhibitor on the surface of friction pairs.Adsorption experiments on lubricating oil containing both antiwear and anticorrosion additives were carried out and the UV absorbance of lubricating oil samples before and after the experiments was measured to determine the difference in the UV absorbance among lubricating oil samples with the same mass fraction of anticorrosion additive and different mass fractions of antiwear additive.By measuring the ultraviolet spectral absorbance of lubricating oil samples and calculating the adsorbed quantity of anticorrosion additive in the interfacial film it was possible to determine the influence of antiwear additive on the quantity of adsorbed anticorrosion additive on the surface of friction pairs and verify the competitive adsorption relationship between the antiwear additive and the anticorrosion additive.展开更多
Biomedical magnesium is an ideal material for hard tissue repair and replacement.However,its rapid degradation and infection after implantation significantly hindersclinical applications.To overcome these two critical...Biomedical magnesium is an ideal material for hard tissue repair and replacement.However,its rapid degradation and infection after implantation significantly hindersclinical applications.To overcome these two critical drawbacks,we describe an integrated strategybased on the changes in pH and Mg^(2+)triggered by magnesiumdegradation.This system can simultaneously offer anticorrosion and antibacterial activity.First,nanoengineered peptide-grafted hyperbranched polymers(NPGHPs)with excellent antibacterial activity were introduced to sodium alginate(SA)to construct a sensitive NPGHPs/SA hydrogel.The swelling degree,responsiveness,and antibacterial activity were then investigated,indicating that the system can perform dual stimulation of pH and Mg^(2+)with controllable antimicrobial properties.Furthermore,an intelligent platform was constructed by coating hydrogels on magnesium with polydopamine as the transition layer.The alkaline environment generated by the corrosion of magnesium reduces the swelling degree of the coatingso that the liquid is unfavorable for contacting the substrate,thus exhibiting superior corrosion resistance.Antibacterial testing shows that the material can effectively fight against bacteria,while hemolytic and cytotoxicity testing suggest that it is highly biocompatible.Thus,this work realizes the smart integration of anticorrosion and antibacterial properties of biomedical magnesium,thereby providing broader prospects for the use of magnesium.展开更多
基金the below mentioned organisation:Key Research and Development Special Project of Henan Provincial Science and Technology(222102230025)Key Research and Development Special Project of Henan Provincial Science and Technology(232102231015)+2 种基金Key Research and Development Special Project of Henan Provincial Science and Technology(232102231011)Natural Science Foundation of Henan Province(No.004053100)Major Science Research Project of High Education of Henan Province(No.23B430016).
文摘Electroactive anticorrosion coatings are specialized surface treatments that prevent or minimize corrosion. Thestudy employs strategic thermodynamic equilibriumcalculations to pioneer a novel factor in corrosion protection.A first-time proposal, the total acidity (TA) potential of the hydrogen (pH) concept significantly shapes medicalmagnesium alloys. These coatings are meticulously designed for robust corrosion resistance, blending theoreticalinsights and practical applications to enhance our grasp of corrosion prevention mechanisms and establisha systematic approach to coating design. The groundbreaking significance of this study lies in its innovativeintegration of the TA/pH concept,which encompasses the TA/pH ratio of the chemical environment. This approachsurpasses convention by acknowledging the intricate interplay between the acidity and pH levels within thecoating formulation, thereby optimizing metal-phosphate-based conversion coatings and transforming corrosionmitigation strategies. To authenticate the TA/pH concept, the study comprehensively compares its findings withexisting research, rigorously validating the theoretical framework and reinforcing the correlates among TA/pHvalues and observed corrosion resistance in the coatings. The influence of mutations that occur naturally inthe detergent solution on persistent phosphorus changes is shown by empirical confirmation, which improvescorrosion resistance. This realization advances the field ofmaterials and the field’s knowledge of coated generation,particularly anticorrosion converter layers.
基金the Surface Project of Local Development in Science and Technology Guided by Central Government(No.2021ZYD0041)Natural Science Foundation of Shandong Province(No.ZR2019YQ24)+2 种基金Taishan Scholars and Young Experts Program of Shandong Province(No.tsqn202103057)the Qingchuang Talents Induction Program of Shandong Higher Education Institution(Research and Innovation Team of Structural-Functional Polymer Composites)Special Financial of Shandong Province(Structural Design of High-efficiency Electromagnetic Wave-absorbing Composite Materials and Construction of Shandong Provincial Talent Teams).
文摘Electromagnetic wave(EMW)absorbing materials have an irreplaceable position in the field of military stealth as well as in the field of electromagnetic pollution control.And in order to cope with the complex electromagnetic environment,the design of multifunctional and multiband high efficiency EMW absorbers remains a tremendous challenge.In this work,we designed a three-dimensional porous structure via the salt melt synthesis strategy to optimize the impedance matching of the absorber.Also,through interfacial engineering,a molybdenum carbide transition layer was introduced between the molybdenum selenide nanoparticles and the three-dimensional porous carbon matrix to improve the absorption behavior of the absorber.The analysis indicates that the number and components of the heterogeneous interfaces have a significant impact on the EMW absorption performance of the absorber due to mechanisms such as interfacial polarization and conduction loss introduced by interfacial engineering.Wherein,the prepared MoSe_(2)/MoC/PNC composites showed excellent EMW absorption performance in C,X,and Ku bands,especially exhibiting a reflection loss of−59.09 dB and an effective absorption bandwidth of 6.96 GHz at 1.9 mm.The coordination between structure and components endows the absorber with strong absorption,broad bandwidth,thin thickness,and multi-frequency absorption characteristics.Remarkably,it can effectively reinforce the marine anticorrosion property of the epoxy resin coating on Q235 steel substrate.This study contributes to a deeper understanding of the relationship between interfacial engineering and the performance of EMW absorbers,and provides a reference for the design of multifunctional,multiband EMW absorption materials.
基金financially supported by the“National Natural Science Foundation of China”(52304072)“Funded by Shandong Postdoctora1 Science Foundation”(SDBX2023019)+1 种基金the“Fundamental Research Funds for the Central Universities”(23CX06022A)the“Applied Research Project of Qingdao Postdoctoral Researchers”(QDBSH20230202010).
文摘The stimuli-responsive anticorrosion coatings have drawn great attention as a prospective corrosion protection approach due to their smart self-repairing properties.In contrast to passive protection mechanism based on post-corrosion microenvironmental changes,a unique active protection strategy based on nanocatalytic oxygen depletion is proposed in this work to inhibit the occurrence of corrosion.Porous FeeNeC catalysts with outstanding oxygen reduction reaction(ORR)activity(half-wave potential of 0.89 V)is firstly synthesized through pre-coordination with organosilane precursor to obtain homogeneously distributed active sites.When this catalyst is introduced into the coating matrix,uniformly distributed FeeNeC not only compensates the defects but plays a crucial role in adsorption and consumption of diffused oxygen in the coating.Under this dual action,the penetration of corrosive medium,especially oxygen,through coating to metal substrate is greatly suppressed,resulting in effective corrosion inhibition and a significant increase in corrosion resistance of the composite coating compared to pure epoxy coating.This work provides a new perspective and the starting point for the design of high-performance smart coating with active anticorrosion properties.
基金the National Natural Science Foundation of China(No.51671050)partially supported by the National Key R&D Program of China(No.2017YFB0305800)the Joint Founds of NSFC Liaoning(No.U1508213).
文摘There is a great challenge to fabricate superhydrophobic coating with excellent mechanical durability and corrosion resistance.Inspired by the pinecone-shaped structure,a novel reduced-graphene oxide(rGO)/Ni composite coating with pinecone-like micro/nanostructures was fabricated successfully on a stainless steel substrate using a simple electrodeposition method combining Ni pre-deposition and an elevated current assistant approach.The results show that the coating is of self-cleaning and superhydrophicity with a water contact angle(CA)of 162.7°±0.8°and a sliding angle(SA)of 2.5°±1.0°.Importantly,the coating still maintains the excellent self-cleaning and superhydrophicity,water CA of 155.8°±1.2°and SA of 5.9°±1.2°,even after 100-cycle mechanical abrasion.Meanwhile,the coating also exhibits good anticorrosion performance in 3.5 wt%NaCl solution,with 99.98%inhibition efficiency.The simple fabrication method may provide a cost-effective way to prepare mechanically durable,anticorrosive,self-cleaning and superhydrophobic coatings on metal substrates.
文摘Corrosion of reinforced concrete structures is a serious problem in ocean engineering. As an orientation of study, anticorrosion coating technique is developed and widely applied, but many problems need to be solved. LSW-2 type anticorrosion coating for maritime reinforced concrete structures is characterized by sea water resistance, salt fog resistance, moisture and heal resistance as well as impermeability to chlorions. The new type coating can be applied to wet concrete surface by conventional construction technique. It is a breakthrough in solving the above mentioned problem. The paper mainly introduces the test results, the property indices, coating procedure, construction technique and economic benefit of Ihe coating.
基金financial support provided by the National Natural Science Foundation of China(Grant No.U1806225)the National Natural Science Foundation of China(Grant No.51908092)the Joint Funds of the National Natural Science Foundation of China-Guangdong(Grant No.U1801254)。
文摘Epoxy resin powder coating has been successfully applied on the corrosion protection of magnesium lithium alloys.However,poor wear resistance and microcracks formed during the solidification have limited it extensive application.There are limited approaches to exploit such anti-corrosion and mechanical properties of magnesium lithium alloys.Herein,the epoxy resin powder coating with polydopamine modified molybdenum disulfide(MoS_(2)@PDA-EP powder coating with 0,0.1,0.2,0.5,1.0 wt.%loading)was well prepared by melt extrusion to investigate its anticorrosion performance and wear resistance.The results revealed that the addition of MoS_(2)@PDA enhanced the adhesion strength between coatings and alloys,wear resistance and corrosion protection of the powder coatings.Among them,the optimum was obtained by 0.2 wt.%MoS_(2)@PDA-EP powder coating which could be attributed to well dispersion and efficient adhesion with coating matrix.To conclude,MoS_(2)@PDA-EP powder coating is meaningfully beneficial for the anticorrosive and wear performance improvement of magnesium lithium alloys.
基金Projects(Y20090108,G20080115)supported by Education Department of Zhejiang and Technology Department of Wenzhou,China
文摘A new surface protection process was developed to magnesium alloy against corrosion in aggressive environments.Firstly,a phosphate coating was formed on rinsed magnesium alloy.Then,powder painting was carried out on the phosphated magnesium alloy.Surface morphologies and phase compositions of the phosphate coating were investigated by X-ray diffraction(XRD) and scanning electron microscope(SEM) .The results show that the phosphate coatings formed in bath containing earth additives at room temperature have dense and fine microstructure.The phosphate coating provides excellent paint adhesion to the magnesium alloy. Salt spray tests indicate that the corrosion resistance of the phosphate coating plus paint could meet the demand of magnesium alloy automobile components in aggressive environments.
文摘In order to investigate the anticorrosion performance of the organic coating/metal system, electrochemical impedance spectra (EIS) were measured in the 3.5wt% NaCl solution, the chemical component and the formation of corrosion products scale were analyzed by laser Raman microspectroscopy, and the pattern of the organic coating/metal system was observed by scanning electron microscopy (SEM). The characteristics and the delamination process of the organic coating/metal system were investigated systematically, and the emphases were on the transportation of the corrosive medium and the changes of the coating/metal interface. The results show that the impedance decreases at the initial immersion, then increases at the middle-immersion, and again decreases at last, which is related to the corrosion products scale. The concentration of Cl in the coating, which destroys the corrosion products scale, increases with the immersion time.
基金the National Natural Science Foundation of China (Nos.41576079,41922040)the Qingdao National Laboratory for Marine Science and Technology (No.QNLM20160RP0413)the AoShan Talent Program Supported by Qingdao National Laboratory for Marine Science and Technology (No.2017ASTCP-ES02)
文摘Smart coating for corrosion protection of metal materials(steel,magnesium,aluminum and their alloys)has drawn great attention because of their capacity to prevent crack propagation in the protective coating by releasing functional molecules(healing agents or corrosion inhibitors)on demand from delivery vehicle,that is,micro/nanocontainer made up of a shell and core material or a coating layer,in a controllable manner.Herein,we summarize the recent achievements during the last 10 years in the field of the micro/nanocontainer with different types of stimuli-responsive properties,i.e.,pH,electrochemical potential,redox,aggressive corrosive ions,heat,light,magnetic field,and mechanical impact,for smart anticorrosion coating.The state-of-the-art design and fabrication of micro/nanocontainer are emphasized with detailed examples.
文摘The aim of this study was to develop a method to prepare WO<sub><span style="font-family:Verdana;">3</span></sub><span style="font-family:Verdana;">-TiO</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;"> film which has high anticorrosion property when it was coated on type 304 stainless steel. A series of WO</span><sub><span style="font-family:Verdana;">3</span></sub><span style="font-family:Verdana;">-modified TiO</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;"> sols were synthesized by peroxo-sol gel method using TiCl</span><sub><span style="font-family:Verdana;">4</span></sub><span style="font-family:Verdana;"> and Na</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;">WO</span><sub><span style="font-family:Verdana;">4</span></sub><span style="font-family:Verdana;"> as the starting materials. TiCl</span><sub><span style="font-family:Verdana;">4</span></sub><span style="font-family:Verdana;"> was converted to Ti(OH)</span><sub><span style="font-family:Verdana;">4</span></sub><span style="font-family:Verdana;"> gel. H</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;">O</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;"> and Na</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;">WO</span><sub><span style="font-family:Verdana;">4</span></sub><span style="font-family:Verdana;"> were added in Ti(OH)</span><sub><span style="font-family:Verdana;">4</span></sub><span style="font-family:Verdana;"> solution and heated at 95<span style="white-space:normal;">°</span>C. The WO</span><sub><span style="font-family:Verdana;">3</span></sub><span style="font-family:Verdana;">-TiO</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;"> sol was transparent, in neutral (pH^7) solution, stable suspension without surfactant, nano-crystallite and no annealing is needed after coating, and very stable for 2 years in stock. WO</span><sub><span style="font-family:Verdana;">3</span></sub><span style="font-family:Verdana;">-TiO</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;"> sol was formed with anatase crystalline structure. These sols were characterized by XRD, TEM, and XPS. The sol was used to coat on stainless steel 304 by dip-coating. The WO</span><sub><span style="font-family:Verdana;">3</span></sub><span style="font-family:Verdana;">-TiO</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;"> was anatase in structure as characterized by X-ray diffraction. There were no WO</span><sub><span style="font-family:Verdana;">3</span></sub><span style="font-family:Verdana;"> XRD peaks in the WO</span><sub><span style="font-family:Verdana;">3</span></sub><span style="font-family:Verdana;">-TiO</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;"> sols, indicating that WO</span><sub><span style="font-family:Verdana;">3</span></sub><span style="font-family:Verdana;"> particles were very small, possibly incorporating into TiO</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;"> structure, providing the amount of WO</span><sub><span style="font-family:Verdana;">3</span></sub><span style="font-family:Verdana;"> was very small. The TiO</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;"> particles were rhombus shape. WO</span><sub><span style="font-family:Verdana;">3</span></sub><span style="font-family:Verdana;">-TiO</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;"> had smaller size area than pure TiO</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;">. The SEM results showed that the film coated on the glass substrate was very uniform. All films were nonporous and dense films. Its hardness reached 2 H after drying at 100<span style="white-space:normal;">°</span>C, and reached 5 H after annealing at 400<span style="white-space:normal;">°</span>C. The WO</span><sub><span style="font-family:Verdana;">3</span></sub><span style="font-family:Verdana;">-TiO</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;"> film coated on 304 stainless steel had better anticorrosion capability than the unmodified TiO</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;"> film under UV light illumination. The optimum weight ratio of TiO</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;">: WO</span><sub><span style="font-family:Verdana;">3</span></sub><span style="font-family:Verdana;"> was 100:4.</span>
文摘Simulated adsorptive experiments using the axletree and lubricating oil containing anticorrosion additive were conducted,and the UV absorbance of the lubricating oil before and after the adsorptive experiments was measured.Through the UV spectral measurements the difference in UV absorbance of the lubricating oil before and after the adsorptive experiments was identified,the adsorbed quantity of anticorrosion additive in the interfacial film between lubricating oil and bearing was calculated using the Lambert-Bell principle to verify the adsorption of corrosion inhibitor on the surface of friction pairs.Adsorption experiments on lubricating oil containing both antiwear and anticorrosion additives were carried out and the UV absorbance of lubricating oil samples before and after the experiments was measured to determine the difference in the UV absorbance among lubricating oil samples with the same mass fraction of anticorrosion additive and different mass fractions of antiwear additive.By measuring the ultraviolet spectral absorbance of lubricating oil samples and calculating the adsorbed quantity of anticorrosion additive in the interfacial film it was possible to determine the influence of antiwear additive on the quantity of adsorbed anticorrosion additive on the surface of friction pairs and verify the competitive adsorption relationship between the antiwear additive and the anticorrosion additive.
基金This work was financially supported by the National Natural Science Foundation of China(no.51671179,51971014)the Excellent teacher ability improvement project(E1E40308).
文摘Biomedical magnesium is an ideal material for hard tissue repair and replacement.However,its rapid degradation and infection after implantation significantly hindersclinical applications.To overcome these two critical drawbacks,we describe an integrated strategybased on the changes in pH and Mg^(2+)triggered by magnesiumdegradation.This system can simultaneously offer anticorrosion and antibacterial activity.First,nanoengineered peptide-grafted hyperbranched polymers(NPGHPs)with excellent antibacterial activity were introduced to sodium alginate(SA)to construct a sensitive NPGHPs/SA hydrogel.The swelling degree,responsiveness,and antibacterial activity were then investigated,indicating that the system can perform dual stimulation of pH and Mg^(2+)with controllable antimicrobial properties.Furthermore,an intelligent platform was constructed by coating hydrogels on magnesium with polydopamine as the transition layer.The alkaline environment generated by the corrosion of magnesium reduces the swelling degree of the coatingso that the liquid is unfavorable for contacting the substrate,thus exhibiting superior corrosion resistance.Antibacterial testing shows that the material can effectively fight against bacteria,while hemolytic and cytotoxicity testing suggest that it is highly biocompatible.Thus,this work realizes the smart integration of anticorrosion and antibacterial properties of biomedical magnesium,thereby providing broader prospects for the use of magnesium.