论文部分内容阅读
利用超音速微粒轰击(SFPB)技术对纯钛(TA2)试样进行了表面纳米化处理,并对SFPB处理后的试样进行不同温度的热处理。通过X射线衍射(XRD)、金相显微镜(OM)、显微硬度计和透射电子显微镜(TEM)分析测试,研究纯钛表面SFPB处理后的纳米化机理及其热稳定性。结果表明:经SFPB处理后试样表层形成了尺寸约为20nm随机取向的等轴晶粒,变形机制以孪生为主,且随层深增加,形变孪晶逐渐由多系转变为单系。纳米化后在450℃热处理时,纳米晶未发生明显粗化,因而具有良好的热稳定性。
The samples of pure titanium (TA2) were surface-nanocrystallized by SFPB and the samples treated with SFPB were heat-treated at different temperatures. The nanofluidization mechanism and thermal stability of pure titanium surface SFPB treated by XRD, OM, microhardness tester and transmission electron microscopy (TEM) were studied. The results show that the equiaxed grains with a random orientation of about 20 nm in size are formed on the surface of the sample after SFPB treatment. The deformation mechanism is dominated by twins. With the increase of layer depth, the deformed twins gradually change from multi-line to single-line. Nanocrystallization at 450 ℃ heat treatment, the nanocrystals did not occur significant coarsening, which has good thermal stability.