论文部分内容阅读
研究不同Al和W含量对四种Co-Al-W三元合金的初熔温度、热处理组织和硬度的影响.结果表明:四种Co-Al-W三元合金的固、液相点温度均超过镍基单晶高温合金液相点温度;在1300℃/8h固溶处理后,三种合金均仅得到γ(fcc)单相组织,而高W合金在晶界和晶内均有μ相Co7W6析出;在800℃/100h和900℃/50h时效处理后,四种合金在基体γ相中均析出L12型γ′相Co3(Al,W),其γ+γ′两相组织形貌与镍基高温合金相似;高W(12%)和高Al(12%)合金分别促进了μ相Co7W6和富Al相析出.综合以上结果并结合时效合金的硬度结果,初步确定了含γ+γ′两相组织的合金成分范围.
The effects of Al and W contents on the melting temperature, heat treatment microstructure and hardness of four Co-Al-W ternary alloys were studied.The results showed that the solidus and liquidus temperature of four kinds of Co-Al-W ternary alloys Which exceeds the liquidus temperature of the nickel base single crystal superalloy. After the solid solution treatment at 1300 ℃ for 8h, all the three alloys have only γ (fcc) single phase structure, while the high-W alloy has the μ phase both in the grain boundary and in the crystal Co7W6 precipitates. After aging treatment at 800 ℃ for 100h and 900 ℃ for 50h, all the four alloys precipitate the γ12 phase γ3 Co3 (Al, W) Ni-based superalloy is similar.The high W (12%) and high Al (12%) alloys respectively promote the precipitation of μ-phase Co7W6 and Al-rich phase.According to the above results and the hardness results of the aged alloys, ’Two-phase structure of the alloy composition range.