摘要
超重力定向凝固是一种有潜力的改善合金力学性能的技术。在足够高的离心加速度下,熔体从层流状态转变为湍流,然后再恢复为层流状态,这势必显著影响凝固前沿的稳定性,从而影响合金的微观结构和力学性能。为了在离心超重力方向上建立一个可控的温度梯度,将多区温度调节系统与坩埚底部的氩气冷却系统相结合,研发了一种超重力定向凝固炉,并在1g和535g条件下进行测试,验证了超重力定向凝固熔铸炉设计方案的可行性。实现了在超重力环境下对于温度梯度和冷却速率的调控。力学性能结果表明,535g样品的力学性能显著优于1g样品,抗拉强度提高了约18%,伸长率约提升76%。证实其在优化合金微观结构及提升力学性能方面的显著优势,为高性能材料制备提供了新方法。
Hypergravity-assisted directional solidification is a promising technique for enhancing the mechanical properties of alloys.Under sufficiently high centrifugal-induced hypergravity acceleration,the melt undergoes a transition from laminar to turbulent flow before reverting to laminar flow,significantly affecting the thermal stability of the solidification front and,consequently,the microstructural evolution and mechanical performance of the alloy.To establish a controllable temperature gradient along the direction of centrifugal hypergravity,a multizone temperature regulation system was combined with an argon gas cooling system at the bottom of the crucible.A hypergravity directional solidification furnace was developed and experimentally evaluated,with tests conducted under 1g and 535g conditions to verify the feasibility of the proposed design for the hypergravity directional solidification casting furnace.By coupling the multizone temperature control method with the crucible bottom cooling method,control over the temperature gradient and cooling rate was achieved under hypergravity conditions.The mechanical property results of the samples indicate that the 535g sample exhibits significantly superior mechanical properties compared with those of the 1g sample,with the tensile strength increasing by approximately 18%and elongation improving by approximately 76%.These results validate the feasibility and effectiveness of the proposed system,demonstrating its significant advantages in refining solidified structures,optimizing alloy microstructures,and enhancing mechanical properties,thereby providing a novel approach for the preparation of high-performance materials.
作者
赵建江
王飞
陈云敏
韦华
ZHAO Jianjiang;WANG Fei;CHEN Yunmin;WEI Hua(Center for Hypergravity Experimental and Interdisciplinary Research,Zhejiang University,Hangzhou 310058,China;College of Civil Engineering and Architecture,Zhejiang University,Hangzhou 310058,China)
出处
《铸造技术》
2025年第5期471-480,共10页
Foundry Technology
基金
国家自然科学基金基础科学中心项目(51988101)。
关键词
超重力
定向凝固
温度梯度
力学性能
hypergravity
directional solidification
temperature gradient
mechanical property
