摘要
研究了真空熔炼时熔体温度对类K445镍基高温合金铸态组织及硬度的影响。结果表明,熔体温度对合金的相种类没有影响,均由树枝状γ基体、弥散分布于基体的γ′相、晶界和枝晶间的γ+γ′共晶、以及γ′′、MC碳化物、少量M3B2硼化物等强化相组成;但随熔体温度的升高,枝晶逐渐细化,一次枝晶轴大量熔断;MC碳化物含量逐渐减少,γ+γ′共晶和γ''相逐渐增多;同时,随熔体温度的升高,合金的硬度不断提高。在1600℃保温时,合金组织中枝晶最细小、γ+γ′共晶和γ′′含量最多、碳化物含量最少,且HB硬度达到最高值3.84GPa。
The effect of melt temperature on the microstructure and Hardness of similar-K445 superalloy has been investigated. The results show that melt temperature has no effect on the sorts of phases. The as-cast microstructure consists of MC carbide, eutectic γ+γ', γ", a spot of M3B2 borides in dendrite regions and secondary γ' phase distributed in the y matrix. However, with the increase of melt temperature, the dendrites get smaller, the content of MC decreases and the contents of eutectic γ+γ' and γ" as well as the hardness of the alloys increase. At the temperature of 1600 ℃, the alloy gets the finest dendrites, the most content of eutectic γ+γ' and γ", the least content of MC and the highest hardness HB 3.84 GPa.
出处
《稀有金属材料与工程》
SCIE
EI
CAS
CSCD
北大核心
2008年第4期744-747,共4页
Rare Metal Materials and Engineering
基金
教育部博士点基金(20050700002)