本文選題：熱鍛模具鋼 + 合金化　； 參考：《鋼鐵研究總院》2017年碩士論文

【摘要】：熱鍛模具鋼通常選用Cr-Mo-V系馬氏體型合金鋼,這類模具鋼因優(yōu)良的綜合性能而備受青睞,例如H13鋼。但過高的Cr含量對熱強(qiáng)性有不利影響,因此目前新鋼種開發(fā)的一種重要的合金化思路是降低Cr含量,并加入Mo與W來提高熱強(qiáng)性。本文以新型6Cr4WMo3V1Co3高熱強(qiáng)性熱鍛模用鋼為研究對象,研究了不同鎢含量(1～3 wt.%)對其微觀組織和力學(xué)性能的影響,并將實驗結(jié)果與傳統(tǒng)H13鋼進(jìn)行對比,最終得出以下主要結(jié)論:1.隨著W含量升高,試驗鋼中共晶碳化物的含量明顯增加,鎢的質(zhì)量分?jǐn)?shù)由1%增加到2%和3%,共晶碳化物含量分別增加29.2%和110.2%,形態(tài)由不規(guī)則狀逐漸轉(zhuǎn)變?yōu)榍驙?類型由M2C逐漸轉(zhuǎn)變?yōu)镸6C。2.W不影響試驗鋼的淬火硬度,試驗鋼經(jīng)1050℃淬火后,硬度可達(dá)60HRC以上,高出H13鋼4HRC;隨著W含量升高,試驗鋼的回火硬度稍有降低,二次硬化峰值硬度可達(dá)58HRC以上,600℃回火后硬度仍有50HRC以上,高出H13鋼 5HRC。3.隨著W含量的上升,試驗鋼抗回火軟化能力先上升后降低。試驗鋼抗回火軟化能力強(qiáng)于H13鋼,650℃回火24h后試驗鋼硬度仍保持在30HRC以上,而H13 鋼只有 22.5HRC。4.隨著W含量的上升,試驗鋼沖擊功先增加后減小,沖擊斷裂方式依次為準(zhǔn)解理斷裂、沿晶斷裂帶淺韌窩以及沿晶斷裂,這主要由共晶碳化物尺寸、形貌和數(shù)量決定的。5.隨著W含量的上升,試驗鋼抗拉強(qiáng)度和屈服強(qiáng)度下降,拉伸斷裂方式為韌性斷裂。與H13鋼相比,600℃回火后試驗鋼抗拉強(qiáng)度提高340Mpa以上,屈服強(qiáng)度提高300Mpa以上。6.在本文研究的新型熱鍛模具鋼中,鎢含量為2%時獲得了最佳的熱穩(wěn)定性和綜合力學(xué)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，

本文編號：2089541