摘要
为增强材料在宽温域下服役的稳定性及减少摩擦与磨损对材料性能的影响,采用Ni60合金粉末作为基体材料,利用放电等离子烧结技术(SPS)制备出了不同LaF3含量的镍基自润滑复合材料。利用HT-1000型高温摩擦磨损试验机、GBS-SmartWLI白光干涉三维轮廓仪、SEM、XRD等对复合材料在大气环境下的宽温域摩擦学性能进行了研究。结果表明,所制备的镍基自润滑材料在宽温域下具有优良的摩擦学性能。复合材料摩擦系数与磨损率从200到800℃的范围内保持在一个较低水平。当LaF3的含量为6%(质量分数)时,平均摩擦系数在200到800℃之间为0.189到0.288且变化范围最小,在600℃下表现最低为0.189,平均磨损率在10-5mm3/N·m数量级,综合表现出最优的摩擦学性能。这是因为LaF3含量为6%的材料在高温下形成了SrSiO3、SrMoO4、La6MoO12等盐类,所形成的盐转移膜一方面防止了对偶材料表面直接接触,另一方面减小了接触薄层的抗剪切强度,从而显著地提高了宽温域环境下材料的稳定性。随着测试温度增加到800℃,由于高温氧化作用使得复合材料摩擦系数略微上升,但仍然保持在0.2左右的较低水平。
In order to enhance the stability of the materials and reduce the influence of friction and wear on the material properties in the wide temperature range,Ni60 alloy powder was used as the matrix materials,and the composite materials of nickel-based self-lubrication with different LaF3 contents were prepared by spark plasma sintering(SPS)technology.The wide-temperature tribological properties of composite materials in air environment were tested by HT-1000 high temperature friction and wear tester,GBS-Smart WLI white light interference three-dimensional profiler,SEM,XRD,etc.Results indicate that the prepared nickel-based self-lubricating composites have excellent tribological properties in a wide temperature range.When the content of LaF3 is 6%,the average friction coefficient varies from0.189 to 0.288 in the temperature range from 200℃to 800℃,the lowest friction coefficient of 0.189 is obtained at 600℃and the average wear rate is on the order of 10-5 mm3/N·m,when the sample exhibits the optimal tribological properties.It is because SrSi03,SrMoO4,La6 MoO12 are formed at a high temperature of the composite materials with the content of 6%,the direct contact of the surface is prevented by the formed salt transfer films and the shear strength of the contact layer is reduced,thereby the stability of the material being improved significantly in a wide temperature range.As the test temperature is increased to 800℃,the friction coefficient of the composite increases slightly due to high temperature oxidations,but remains at a low level of 0.2.
作者
肖荣振
曹雪
安国升
冯力
Xiao Rongzhen;Cao Xue;An Guosheng;Feng Li(State Key Laboratory of Advanced Processing and Recycling of Non-ferrous Metals,Lanzhou University of Technology,Lanzhou 730050,China)
出处
《稀有金属材料与工程》
SCIE
EI
CAS
CSCD
北大核心
2020年第1期267-273,共7页
Rare Metal Materials and Engineering
基金
国家自然科学基金(11504149)。
关键词
放电等离子烧结
摩擦磨损
宽温域
高温自润滑
spark plasma sintering
friction and wear
wide temperature range
high temperature self-lubrication
