水分对核废料硼硅酸盐玻璃摩擦磨损性能的影响

Effect of Water on Friction and Wear Behaviors of Nuclear Waste Borosilicate Glass

使用环境可控的摩擦磨损试验机,以不锈钢球作为对摩副,探究了不同水分环境下(干燥、相对湿度RH20%、RH50%、RH70%和液态水)核废料硼硅酸盐玻璃的磨损规律和机理.研究发现:硼硅酸盐玻璃基底和不锈钢球的稳态摩擦系数、磨损量和次表面损伤随着环境湿度的增加逐渐减小,而在液态水环境中,玻璃界面的稳态摩擦系数、磨损量以及次表面损伤深度均远小于干燥和潮湿空气.核废料硼硅酸盐玻璃在干燥环境下的磨损形式以黏着磨损和磨粒磨损为主;在潮湿和液态水环境下,玻璃的磨损行为由水分诱导的摩擦化学磨损主导.玻璃表面吸附水分子诱导的摩擦化学作用和润滑作用,造成了玻璃在液态水环境中的磨损量和次表面损伤均远小于干燥和潮湿环境下.

Using an environment-controlled tribometer,the effect of water on friction and wear behaviors of nuclear borosilicate glass were studied by rubbing against a stainless steel ball under various water environments(dry,RH20%,RH50%,RH70%,and liquid water).The experimental results show that the steady-state friction coefficient,wear volume,and the subsurface damage of borosilicate glass substrate decrease with the increasing in relative humidity.Furthermore,in presence of liquid water,the steady-state friction coefficient of glass interface was the lowest among all the cases,accompanying with the lowest wear volume and subsurface damage depth.In dry environments,the wear behaviors of the nuclear borosilicate glass are mainly dominated by adhesive wear and abrasive wear,while it is dominated by water-induced tribochemical reactions when the tests are performed in humid air and liquid water environments.Due to the water-induced tribochemical products and the lubricity of water molecules adsorbed on glass surface,the wear and subsurface damage of the glass in the liquid water are much milder than that in dry and humid environments.