Effect of titanium and nitrogen inoculation on the microstructure, mechanical properties and abrasive wear resistance of Hadfield Steels

Abstract The effect of titanium and nitrogen addition on Hadfield steels was investigated. In order to do this, two grades of steels were produced in terms of titanium and nitrogen addition. The final samples had their microstructure characterized and their mechanical properties were evaluated by uniaxial tensile and Charpy impact tests. Furthermore, the wear resistance was measured by dry sand rubber wheel abrasive tests. Microscopy analyses demonstrated that the precipitation of titanium carbonitrides resulted in a coarse microstructure, with large columnar grains coexisting with equiaxed ones. Consequently, these samples presented lower mechanical properties in comparison with the samples without titanium and nitrogen, which showed a finer microstructure. On the other hand, the presence of hard Ti(C, N) precipitates in the microstructure improved the abrasive wear performance of the steel during the abrasive tests.

摘要 本研究探究了钛与氮添加对哈德菲尔德钢（Hadfield steels）的影响。为此，通过调控钛与氮的添加量制备了两种不同牌号的钢材。对最终制备的试样开展显微组织表征，并通过单轴拉伸试验与夏比冲击试验评估其力学性能。此外，采用干砂橡胶轮磨料磨损试验测试了试样的耐磨性能。显微分析结果表明，钛碳氮化物的析出会导致显微组织粗化，粗大的柱状晶与等轴晶共存。因此，与未添加钛与氮、显微组织更为细密的试样相比，此类试样的力学性能更低。但另一方面，显微组织中硬质Ti(C,N)析出相的存在，提升了钢材在磨料磨损试验中的耐磨性能。