Zhang Yuqi, Zhang Cheng, Li Fei, Wang Zhou, Wang Xiaodong, Wang Changji, Zhang Cheng, Huang Jinfeng, Mao Feng, Chen Chong, Jiang Tao, Wei Shizhong, Xiong Mei, Hu Jinmeng
School of Materials Science and Engineering, Henan University of Science and Technology, Luoyang 471003, China.
National Joint Engineering Research Center for Abrasion Control and Molding of Metal Materials, Henan University of Science and Technology, Luoyang 471003, China.
Materials (Basel). 2022 Jul 25;15(15):5145. doi: 10.3390/ma15155145.
The oxidation of 3Cr3Mo2NiW and 3CrNi3Mo steels was studied at 600 °C in air, and the test results suggest that the parabolic rate law fitted the oxidation kinetics of both steels. The microstructure, morphology, structure, and phase composition of the oxide film cross-sectional layers of the two Cr-Ni-Mo hot-work die steels were analyzed using scanning electron microscopy (SEM), energy-dispersive spectrometry (EDS), and X-ray diffraction (XRD). The influences of Cr, Ni, and Mo on the high-temperature oxidation resistance of the two Cr-Ni-Mo hot-work die steels are discussed, and the oxidation mechanism is summarized. Heat-treated samples were analyzed using electron backscattered diffraction (EBSD) to obtain inverse pole figures (IPFs) and average sample grain sizes, and the percentages of twin grain boundaries (TGBs) (θ = 60°) were also measured. After heat treatment, recrystallization was observed in both steels with a large portion of twin grain boundaries. After 10 h of oxidation, the dense chromium-rich oxide layer that formed in the inner oxide layer of 3Cr3Mo2NiW steel effectively prevented the continuation of oxidation. The inner oxide layer in 3CrNi3Mo steel formed an adhesion layer with a network structure composed mainly of Ni- and Cr-rich spinel oxide, without forming a barrier to prevent oxidation.
研究了3Cr3Mo2NiW钢和3CrNi3Mo钢在600℃空气中的氧化行为，试验结果表明抛物线速率定律适用于这两种钢的氧化动力学。利用扫描电子显微镜（SEM）、能谱仪（EDS）和X射线衍射仪（XRD）分析了两种Cr-Ni-Mo热作模具钢氧化膜横截面层的微观结构、形貌、组织和相组成。讨论了Cr、Ni和Mo对两种Cr-Ni-Mo热作模具钢高温抗氧化性能的影响，并总结了氧化机理。对热处理后的样品进行电子背散射衍射（EBSD）分析，得到反极图（IPF）和平均样品晶粒尺寸，并测量孪晶界（TGBs）（θ = 60°）的百分比。热处理后，两种钢均发生再结晶，且存在大量孪晶界。氧化10 h后，3Cr3Mo2NiW钢内氧化层中形成的致密富铬氧化层有效地阻止了氧化的继续进行。3CrNi3Mo钢的内氧化层形成了一个主要由富Ni和富Cr尖晶石氧化物组成的网络结构的粘附层，没有形成阻止氧化的阻挡层。
