The oxidation of the Electrodeposited RE-Ni-W-P-SiC Composite materials at high temperature is investigated. The results show that during high temperature oxidation the relationship between the mass change of pure Ni,...The oxidation of the Electrodeposited RE-Ni-W-P-SiC Composite materials at high temperature is investigated. The results show that during high temperature oxidation the relationship between the mass change of pure Ni, Ni-W-P, Ni-W-P-SiC or RE-Ni-W-P-SiC coatings and the oxidation time follows a mixed curve, i.e. it is approximately a linear relationship when the oxidation time is less than 60 mins while it is a power function relationship when the oxidation time is over 60 mins. The order for the oxidation rate of the four coatings is Ni> Ni-W-P> Ni-W-P-SiC>RE-Ni-W-P-SiC. The mass change of Ni-W-P, Ni-W-P-SiC or RE-Ni-W-P-SiC coatings increases exponentially with a rise of oxidation temperature. The high temperature-oxidation resistance of RE-Ni-W-P-SiC composite material is 3-4 times than that of Ni-W-P alloy coating. The cross section morphologies and X-ray diffraction patterns indicate that the high temperature-oxidation resistance of RE-Ni-W-P-SiC composite coating is better than any other coatings.展开更多
Ni-W-GO composite coatings were successfully plated on 45# steel substrate by co-electrodeposition technique in a Ni-W electrolyte solution, with different contents of graphene oxide (GO) nanoparticles in suspen? sion...Ni-W-GO composite coatings were successfully plated on 45# steel substrate by co-electrodeposition technique in a Ni-W electrolyte solution, with different contents of graphene oxide (GO) nanoparticles in suspen? sion. The structure, phase composition and surface morphology of as-plated composite coatings were characterized by Raman, X-ray diffraction (XRD), scanning electron microscopy (SEM) attached with energy disperse spectroscopy (EDS), respectively. The hardness and tribological behavior of the present coatings were also evaluated by Vickers Hardness tester and high-speed reciprocating friction and wear tester, and the wear mechanism was discussed as well. The results show that layer-structured GO nanoparticles significantly affect the microstructure and grain size of the Ni-W-GO composite coatings. Meanwhile, GO nanoparticles embedded in Ni- W-GO coatings can obviously improve the hardness and wear resistance in comparison with the corresp on ding Ni- W coatings. The highest microhardness and wear resistance of Ni-W-GO composite coatings are obtained with 0.15 g·L^-1 GO employing.展开更多
利用两阶段还原法对W Ni Fe复合氧化物粉末进行还原,控制还原工艺的参数制得纳米级W Ni Fe复合粉末。采用XRD对粉末进行物相分析,并计算晶粒尺寸;采用高倍SEM观察粉末形貌;对复合粉末的费氏粒度、比表面面积、氧含量等进行测定与分析,...利用两阶段还原法对W Ni Fe复合氧化物粉末进行还原,控制还原工艺的参数制得纳米级W Ni Fe复合粉末。采用XRD对粉末进行物相分析,并计算晶粒尺寸;采用高倍SEM观察粉末形貌;对复合粉末的费氏粒度、比表面面积、氧含量等进行测定与分析,研究还原温度和还原时间对粉末性能的影响。研究结果表明:当还原温度高于600℃时制得的复合粉末由W和(Ni,Fe)两相组成;粉末颗粒呈球形或近球形;还原温度和还原时间都对W Ni Fe复合粉末的性能有显著影响,当还原温度为700℃,还原时间为90min时,制备的颗粒为平均费氏粒度低于0.65μm,平均BET粒度小于100nm,晶粒粒径小于30nm,粉末氧含量小于0.23%的纳米级W Ni Fe复合粉末。展开更多
研究了RE Ni W P SiC PTFE复合镀层的抗氧化性。结果表明 :RE Ni W P SiC PTFE复合镀层随着氧化温度的升高 ,氧化膜的重量增加 ,但在 80 0°C以下氧化温度对镀层的增重不显著 ;80 0°C以上 ,镀层的增重迅速增加。通过对三种镀...研究了RE Ni W P SiC PTFE复合镀层的抗氧化性。结果表明 :RE Ni W P SiC PTFE复合镀层随着氧化温度的升高 ,氧化膜的重量增加 ,但在 80 0°C以下氧化温度对镀层的增重不显著 ;80 0°C以上 ,镀层的增重迅速增加。通过对三种镀层抗氧化性能的比较可知 ,RE Ni W P SiC PTFE镀层的抗氧化性不如Ni W P、Ni W P SiC及RE Ni W P SiC三种镀层好。展开更多
文摘The oxidation of the Electrodeposited RE-Ni-W-P-SiC Composite materials at high temperature is investigated. The results show that during high temperature oxidation the relationship between the mass change of pure Ni, Ni-W-P, Ni-W-P-SiC or RE-Ni-W-P-SiC coatings and the oxidation time follows a mixed curve, i.e. it is approximately a linear relationship when the oxidation time is less than 60 mins while it is a power function relationship when the oxidation time is over 60 mins. The order for the oxidation rate of the four coatings is Ni> Ni-W-P> Ni-W-P-SiC>RE-Ni-W-P-SiC. The mass change of Ni-W-P, Ni-W-P-SiC or RE-Ni-W-P-SiC coatings increases exponentially with a rise of oxidation temperature. The high temperature-oxidation resistance of RE-Ni-W-P-SiC composite material is 3-4 times than that of Ni-W-P alloy coating. The cross section morphologies and X-ray diffraction patterns indicate that the high temperature-oxidation resistance of RE-Ni-W-P-SiC composite coating is better than any other coatings.
基金financially supported by the Natural Science Foundation of Jiangxi Province (Nos. 20161BAB216121,20161BAB206136 and GJJ150638)the National Natural Science Foundation of China (No. 91326203)
文摘Ni-W-GO composite coatings were successfully plated on 45# steel substrate by co-electrodeposition technique in a Ni-W electrolyte solution, with different contents of graphene oxide (GO) nanoparticles in suspen? sion. The structure, phase composition and surface morphology of as-plated composite coatings were characterized by Raman, X-ray diffraction (XRD), scanning electron microscopy (SEM) attached with energy disperse spectroscopy (EDS), respectively. The hardness and tribological behavior of the present coatings were also evaluated by Vickers Hardness tester and high-speed reciprocating friction and wear tester, and the wear mechanism was discussed as well. The results show that layer-structured GO nanoparticles significantly affect the microstructure and grain size of the Ni-W-GO composite coatings. Meanwhile, GO nanoparticles embedded in Ni- W-GO coatings can obviously improve the hardness and wear resistance in comparison with the corresp on ding Ni- W coatings. The highest microhardness and wear resistance of Ni-W-GO composite coatings are obtained with 0.15 g·L^-1 GO employing.
文摘利用两阶段还原法对W Ni Fe复合氧化物粉末进行还原,控制还原工艺的参数制得纳米级W Ni Fe复合粉末。采用XRD对粉末进行物相分析,并计算晶粒尺寸;采用高倍SEM观察粉末形貌;对复合粉末的费氏粒度、比表面面积、氧含量等进行测定与分析,研究还原温度和还原时间对粉末性能的影响。研究结果表明:当还原温度高于600℃时制得的复合粉末由W和(Ni,Fe)两相组成;粉末颗粒呈球形或近球形;还原温度和还原时间都对W Ni Fe复合粉末的性能有显著影响,当还原温度为700℃,还原时间为90min时,制备的颗粒为平均费氏粒度低于0.65μm,平均BET粒度小于100nm,晶粒粒径小于30nm,粉末氧含量小于0.23%的纳米级W Ni Fe复合粉末。
文摘研究了RE Ni W P SiC PTFE复合镀层的抗氧化性。结果表明 :RE Ni W P SiC PTFE复合镀层随着氧化温度的升高 ,氧化膜的重量增加 ,但在 80 0°C以下氧化温度对镀层的增重不显著 ;80 0°C以上 ,镀层的增重迅速增加。通过对三种镀层抗氧化性能的比较可知 ,RE Ni W P SiC PTFE镀层的抗氧化性不如Ni W P、Ni W P SiC及RE Ni W P SiC三种镀层好。