钨对新型热锻模具钢组织和力学性能影响

发布时间：2018-07-02 08:34

  本文选题：热锻模具钢 + 合金化　； 参考：《钢铁研究总院》2017年硕士论文

【摘要】：热锻模具钢通常选用Cr-Mo-V系马氏体型合金钢,这类模具钢因优良的综合性能而备受青睐,例如H13钢。但过高的Cr含量对热强性有不利影响,因此目前新钢种开发的一种重要的合金化思路是降低Cr含量,并加入Mo与W来提高热强性。本文以新型6Cr4WMo3V1Co3高热强性热锻模用钢为研究对象,研究了不同钨含量(1～3 wt.%)对其微观组织和力学性能的影响,并将实验结果与传统H13钢进行对比,最终得出以下主要结论:1.随着W含量升高,试验钢中共晶碳化物的含量明显增加,钨的质量分数由1%增加到2%和3%,共晶碳化物含量分别增加29.2%和110.2%,形态由不规则状逐渐转变为球状,类型由M2C逐渐转变为M6C。2.W不影响试验钢的淬火硬度,试验钢经1050℃淬火后,硬度可达60HRC以上,高出H13钢4HRC;随着W含量升高,试验钢的回火硬度稍有降低,二次硬化峰值硬度可达58HRC以上,600℃回火后硬度仍有50HRC以上,高出H13钢 5HRC。3.随着W含量的上升,试验钢抗回火软化能力先上升后降低。试验钢抗回火软化能力强于H13钢,650℃回火24h后试验钢硬度仍保持在30HRC以上,而H13 钢只有 22.5HRC。4.随着W含量的上升,试验钢冲击功先增加后减小,冲击断裂方式依次为准解理断裂、沿晶断裂带浅韧窝以及沿晶断裂,这主要由共晶碳化物尺寸、形貌和数量决定的。5.随着W含量的上升,试验钢抗拉强度和屈服强度下降,拉伸断裂方式为韧性断裂。与H13钢相比,600℃回火后试验钢抗拉强度提高340Mpa以上,屈服强度提高300Mpa以上。6.在本文研究的新型热锻模具钢中,钨含量为2%时获得了最佳的热稳定性和综合力学性能。
[Abstract]:Cr-Mo-V martensite alloy steel is usually used in hot forging die steel. This kind of die steel is favored for its excellent comprehensive properties, such as H13 steel. However, too high Cr content has a negative effect on thermal strength. Therefore, an important way of alloying new steel at present is to reduce Cr content and add Mo and W to improve thermal strength. In this paper, the effect of different tungsten content (1wt.%) on microstructure and mechanical properties of 6Cr4WMo3V1Co3 hot forging die steel with high thermal strength is studied. The experimental results are compared with that of traditional H13 steel. The main conclusions are as follows: 1: 1. With the increase of W content, the content of eutectic carbides in the test steel increased obviously, the mass fraction of tungsten increased from 1% to 2% and 3%, the content of eutectic carbides increased by 29.2% and 110.2%, respectively, and the shape of eutectic carbides gradually changed from irregular to spherical. The hardness of the test steel changed from M2C to M6C.2.W gradually. After quenching at 1050 鈩，

本文编号：2089541