The fretting wear behavior of 0Cr20Ni32AlTi alloy was investigated with crossed cylinder contact under 80 N at 300 and 400 °C.Wear scar and debris were analyzed systematically by scanning electron microscopy and ...The fretting wear behavior of 0Cr20Ni32AlTi alloy was investigated with crossed cylinder contact under 80 N at 300 and 400 °C.Wear scar and debris were analyzed systematically by scanning electron microscopy and X-ray photoelectron spectroscopy.The results show that the friction logs are mixed fretting regime and gross slip regime with the magnitudes of displacement of 10 and 20 μm,respectively.Severe wear and friction oxidation occur on the material surface.A large number of granular debris produced in the fretting process can be easily congregated and adhered at the contact zone after repeated crushes.The resultant of friction oxidation is mainly composed of Fe3O4,Fe2O3,Cr2O3 and NiO.Temperature and friction are the major factors affecting the oxidation reaction rate.The fretting friction effect can enhance the oxidation reaction activity of surface atoms of 0Cr20Ni32AlTi alloy and reduce the oxidation activation energy.As result,the oxidation reaction rate is accelerated.展开更多
Triboelectric nanogenerator(TENG)is an emerging method for harvesting mechanical energy.In traditional rotary TENGs(RTENGs),the mutual friction between positive and negative friction materials significantly shortens t...Triboelectric nanogenerator(TENG)is an emerging method for harvesting mechanical energy.In traditional rotary TENGs(RTENGs),the mutual friction between positive and negative friction materials significantly shortens their operational lifespan.The non-contact triboelectric nanogenerator addresses this issue effectively;however,its low output performance still limits practical applications.In this work,we introduce a novel charge supplementation strategy to enhance the performance of NCRTENGs.This strategy involves directly affixing wool between the Cu electrodes of the NCR-TENG,while the negative friction material is modified by doping with MXene,resulting in a substantial enhancement of output.The voltage,current,and charge transfer increased by 4.5,4.5,and 4.8 times,respectively,reaching 451 V,21.2μA and 47 nC.Furthermore,NCR-TENG demonstrates remarkable stability,maintaining 100%output characteristics after 33,600 cycles.The output power reaches2.3 mW when load resistance is 107Ω.It takes only 0.8 s to charge a 0.1μF capacitor to 10 V.This work not only improves the output performance of the NCR-TENG but also retains the capability of low-speed startup while maintaining high wear resistance.The simple and effective charge supplementation strategy proposed here provides a new perspective for further improving the output characteristics of NCR-TENGs.NCR-TENG has potential application prospects in harvesting wind energy to power traffic flow sensor networks,detecting environmental and vehicle information,and optimizing traffic signal control.展开更多
The roller is one of the main parts of a high-pressure grinding roller, which is a type of highly efficient ore crushing equipment. Its working life is strongly affected by the materials used. In this paper, a new kin...The roller is one of the main parts of a high-pressure grinding roller, which is a type of highly efficient ore crushing equipment. Its working life is strongly affected by the materials used. In this paper, a new kind of roller material, the high-vanadium alloy steel （HVAS）, was investigated. The results showed that the as-cast microstructures of the HVAS roller contained martensite, residual austenite, and alloy carbides. The HVAS sample quenched at 1,080 ℃ had a high hardness, and it had much higher compressive strength and abrasive wear resistance after tempering at 560 ℃ for 30 rain. The mechanical properties of the HVAS are more sufficient than the existing roller materials, which are feasible for larger machine design.展开更多
The impact corrosion-abrasion properties and mechanism of high manganese steel were investigated under different impact energies. The result shows that the wearability of the steel decreases with the increase of the i...The impact corrosion-abrasion properties and mechanism of high manganese steel were investigated under different impact energies. The result shows that the wearability of the steel decreases with the increase of the impact energy. The dominant failure mechanism at a lower impact energy is the rupture of extrusion edge along root and a slight shallow-layer spalling. It transforms to shallow-layer fatigue flaking along with serious corrosion-abrasion when the impact energy is increased, and finally changes to bulk flaking of hardened laver caused by deeo work-hardening and heaw corrosion-abrasion.展开更多
通过调整高速钢成分和采用RE K Na复合变质处理,改变了共晶碳化物的形态和分布,使铸造高速钢冲击韧度提高69 9%,热疲劳抗力也明显改善。变质处理高速钢导辊使用中不粘钢、不破碎、不剥落,使用寿命比高镍铬合金铸钢和Cr12MoV锻钢导辊提高...通过调整高速钢成分和采用RE K Na复合变质处理,改变了共晶碳化物的形态和分布,使铸造高速钢冲击韧度提高69 9%,热疲劳抗力也明显改善。变质处理高速钢导辊使用中不粘钢、不破碎、不剥落,使用寿命比高镍铬合金铸钢和Cr12MoV锻钢导辊提高2～3倍。展开更多
基金Project (51075342) supported by the National Natural Science Foundation of ChinaProject (2007CB714704) supported by the National Basic Research Program of China
文摘The fretting wear behavior of 0Cr20Ni32AlTi alloy was investigated with crossed cylinder contact under 80 N at 300 and 400 °C.Wear scar and debris were analyzed systematically by scanning electron microscopy and X-ray photoelectron spectroscopy.The results show that the friction logs are mixed fretting regime and gross slip regime with the magnitudes of displacement of 10 and 20 μm,respectively.Severe wear and friction oxidation occur on the material surface.A large number of granular debris produced in the fretting process can be easily congregated and adhered at the contact zone after repeated crushes.The resultant of friction oxidation is mainly composed of Fe3O4,Fe2O3,Cr2O3 and NiO.Temperature and friction are the major factors affecting the oxidation reaction rate.The fretting friction effect can enhance the oxidation reaction activity of surface atoms of 0Cr20Ni32AlTi alloy and reduce the oxidation activation energy.As result,the oxidation reaction rate is accelerated.
基金supported by the Natural Science Foundation for Young Scientists of Shanxi Province(Grant No.202203021212127)。
文摘Triboelectric nanogenerator(TENG)is an emerging method for harvesting mechanical energy.In traditional rotary TENGs(RTENGs),the mutual friction between positive and negative friction materials significantly shortens their operational lifespan.The non-contact triboelectric nanogenerator addresses this issue effectively;however,its low output performance still limits practical applications.In this work,we introduce a novel charge supplementation strategy to enhance the performance of NCRTENGs.This strategy involves directly affixing wool between the Cu electrodes of the NCR-TENG,while the negative friction material is modified by doping with MXene,resulting in a substantial enhancement of output.The voltage,current,and charge transfer increased by 4.5,4.5,and 4.8 times,respectively,reaching 451 V,21.2μA and 47 nC.Furthermore,NCR-TENG demonstrates remarkable stability,maintaining 100%output characteristics after 33,600 cycles.The output power reaches2.3 mW when load resistance is 107Ω.It takes only 0.8 s to charge a 0.1μF capacitor to 10 V.This work not only improves the output performance of the NCR-TENG but also retains the capability of low-speed startup while maintaining high wear resistance.The simple and effective charge supplementation strategy proposed here provides a new perspective for further improving the output characteristics of NCR-TENGs.NCR-TENG has potential application prospects in harvesting wind energy to power traffic flow sensor networks,detecting environmental and vehicle information,and optimizing traffic signal control.
基金supported by the National High Technology Research and Development Program (No. 2012AA03A508)Project of Science and Technology Plan of Shenyang City (No. F12-027-2-00)Project of Science and Technology Plan of Liaoning Province (No. LNSBQ4-2010921055)
文摘The roller is one of the main parts of a high-pressure grinding roller, which is a type of highly efficient ore crushing equipment. Its working life is strongly affected by the materials used. In this paper, a new kind of roller material, the high-vanadium alloy steel （HVAS）, was investigated. The results showed that the as-cast microstructures of the HVAS roller contained martensite, residual austenite, and alloy carbides. The HVAS sample quenched at 1,080 ℃ had a high hardness, and it had much higher compressive strength and abrasive wear resistance after tempering at 560 ℃ for 30 rain. The mechanical properties of the HVAS are more sufficient than the existing roller materials, which are feasible for larger machine design.
基金the Doctoral Authorization Point Foundation of Education Ministry of China(No.20040359004)the Major Project Foundation of Education Office of Anhui Province(No.KJ2007A060)
文摘The impact corrosion-abrasion properties and mechanism of high manganese steel were investigated under different impact energies. The result shows that the wearability of the steel decreases with the increase of the impact energy. The dominant failure mechanism at a lower impact energy is the rupture of extrusion edge along root and a slight shallow-layer spalling. It transforms to shallow-layer fatigue flaking along with serious corrosion-abrasion when the impact energy is increased, and finally changes to bulk flaking of hardened laver caused by deeo work-hardening and heaw corrosion-abrasion.
