A porosity-free and contamination-free surface layer with grain sizes ranging from nanometer to micrometer in Fe samples was obtained by surface mechanical attrition treatment (SMAT) technique. Mechanical and wear pro...A porosity-free and contamination-free surface layer with grain sizes ranging from nanometer to micrometer in Fe samples was obtained by surface mechanical attrition treatment (SMAT) technique. Mechanical and wear properties of the surface layer in the SMATed and annealed Fe samples were measured by means of nanoindentation and nanoscratch tests, respectively. Experimental results showed that the hardness of the surface layer in the SMATed Fe sample increased evidently due to the grain refinement. The elastic moduli of the surface layers in the SMATed and annealed Fe samples were unchanged, independent of grain size in the present grain size regime. Compared with the original Fe sample, the wear resistance enhanced and the coefficient of friction decreased in the surface layer of the SMATed Fe sample.展开更多
2010年l2月，斯蒂芬和韦恩两兄弟创立了最受欢迎的网站之一：crazythingsparentstext．com，吸引了数百万网友的点阅和参与。2011年他们更出版了一本名为《调皮爸妈的疯狂短信》（Crazy Things Parents Text）的短信书，收录了几百条有...2010年l2月，斯蒂芬和韦恩两兄弟创立了最受欢迎的网站之一：crazythingsparentstext．com，吸引了数百万网友的点阅和参与。2011年他们更出版了一本名为《调皮爸妈的疯狂短信》（Crazy Things Parents Text）的短信书，收录了几百条有关父母与孩子的搞笑短信。看着这些调皮幽默的短信，我们不禁感叹：“这帮可爱的老顽童啊!”展开更多
基金Financial support from the National Natural Science Foundation of China,the Ministry of Science and Technology of China(Grant G1999064505)NEDO International Joint Research Grant Program(01MB5)Ministry of Research of France(Grant 2001882,CPER EN2040)is acknowledged.
文摘A porosity-free and contamination-free surface layer with grain sizes ranging from nanometer to micrometer in Fe samples was obtained by surface mechanical attrition treatment (SMAT) technique. Mechanical and wear properties of the surface layer in the SMATed and annealed Fe samples were measured by means of nanoindentation and nanoscratch tests, respectively. Experimental results showed that the hardness of the surface layer in the SMATed Fe sample increased evidently due to the grain refinement. The elastic moduli of the surface layers in the SMATed and annealed Fe samples were unchanged, independent of grain size in the present grain size regime. Compared with the original Fe sample, the wear resistance enhanced and the coefficient of friction decreased in the surface layer of the SMATed Fe sample.
文摘2010年l2月，斯蒂芬和韦恩两兄弟创立了最受欢迎的网站之一：crazythingsparentstext．com，吸引了数百万网友的点阅和参与。2011年他们更出版了一本名为《调皮爸妈的疯狂短信》（Crazy Things Parents Text）的短信书，收录了几百条有关父母与孩子的搞笑短信。看着这些调皮幽默的短信，我们不禁感叹：“这帮可爱的老顽童啊!”
