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利用透射电子显微镜研究了快速凝固Al-4Zr-2Ti合金的组织结构.结果表明:快凝合金的显微硬度与其显微组织密切相关,快凝合金激冷态组织显示出单一相--过饱和Al基固溶体,此时显微硬度为220 HV.快凝合金经420 ℃退火4 h,具有立方结构的亚稳相L12-Al3(Zr,Ti)析出,此时显微硬度达到峰值260 HV.而经420 ℃退火20 h...
摘要: After the pandemic, more downtown building owners and designers are seeking to lure back tenants with properties that blur the lines between work and home life. When the recent pandemic began, much of our country's in-office workforce grew accustomed to taking calls and filing reports fr...