(太原理工大學(xué)表面工程研究所，太原 030024)
摘 要: 研究了W, Co, Ni對(duì)時(shí)效合金強(qiáng)度和韌性的影響。結(jié)果表明：高Co的Fe-W-Co合金有強(qiáng)的時(shí)效硬化能力，但其韌性較低。以Ni取代部分Co之后，合金的韌性得到大的提高。Fe-W-Co合金的Co量約23%，W, Mo總量超過18%時(shí)，硬度增加甚少，韌性損害較大，而Fe-W-Co-Ni的Co當(dāng)量達(dá)23%，W, Mo總量達(dá)24%時(shí)獲得最佳的強(qiáng)度和韌性的配合。萃取化合物的X射線衍射(XRD) 分析表明，時(shí)效合金的主要金屬間化合物是Fe3W2型，還有Fe7W6和Fe2W型化合物。 淬火態(tài)、退火態(tài)萃取物的化學(xué)分析表明，時(shí)效合金中，W, Mo主要存在于化合 物中 ，而Co, Ni主要存在于固溶體中。時(shí)效硬化主要通過W, Mo金屬間化合物的析出引起。而Co, Ni主要通過影響析出相的數(shù)量、析出物形態(tài)及分布狀態(tài)來影響時(shí)效硬化
關(guān)鍵字: 強(qiáng)度 韌性 固溶體 金屬間化合物 時(shí)效硬化
（Research Institute of Surface Engineering,Taiyuan University of Technology, Taiyuan 030024, P. R. China）
Abstract:The influence of W, Co and Ni on strength and toughness of ageing alloys was studied. The results indicated that the Fe-W-Co alloy with higher cobalt possesses stronger ability of age-hardening but lower toughness. After cobalt is partly substituted by nickel, the toughness of alloy is greatly raised . The hardness almost doesn't increase and toughness decreases greatly, when the total content of (W+Mo) is over 18% in Fe-W-Co alloy with 23% Co, but when the cobalt equivalent reached 23% and the total quantity of W and Mo reaches about 24% in F e-W-Co-Ni alloy, the optimum combination of strength and toughness is obtained. X-ray d iffraction (XRD) result for extraction compounds showed that Fe3W2 type is the main intermetallic compound in ageing alloy, and there are also compounds of Fe7W6 type and Fe2W type. The chemical analysis of extraction compounds showed that the majority of W and Mo exists in compounds, while the majority of Co and Ni exists in solid solution. The age-hardening is mainly caused by deposition of intermetallic compounds of W and Mo. Co and Ni have an effect on age-hardening mainly through affecting quantity, shape and distribution of precipitation phases.
Key words: strength toughness solid solution intermetallic compounds agehardening
