Invention of high performance magnesium alloys with trade-off balancing by multi-scale controlling

通过多尺度控制权衡平衡发明高性能镁合金

• 批准号: 11225209
• 负责人: HIGASHI Kenji
• 金额: $ 49.34万
• 依托单位: Osaka Prefecture University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research on Priority Areas
• 财政年份: 1999
• 资助国家: 日本
• 起止时间: 1999 至 2002
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-11225209/
• 关键词: Multi-scale controlling; Trade-off balancing; The first principle molecular dynamics; Refinement processing; Crystallographic orientation control Diffusion bonding; Press formability; Notch sensitivity; 切欠き感受性; 拡散接合; プレス成形性; マルチスケール制御プロセス; トレード

This research purpose is the invention of the high performance magnesium alloys, which are trade-off balanced by multi-scale controlling from electron or atomic level to macroscopic level. The results are summarizes to below.(1)In "the analysis for deformation behavior and an alloy design by the first principle molecular dynamics calculation", the big difference in the critical resolved shear stress between basal and prismatic slip planes, which leads to the brittle-nature of magnesium, was discussed from the results by theoretical calculation on the generalized stacking fault energy in ideal slip deformation of each single crystal. As the result it was found that an addition of Li, Al or Zn could make the difference small. Moreover, the anisotropy of the bonding strength was discussed from the electron density distribution.(2)In "the construction of the materials process for the alloy having an excellent in mechanical property and formability", an improvement in the impact properties … More was attained by the uniform distribution in fine Zr-precipitates and the grain refinement on the Mg-Zn system alloy processed by equal-channel-angular-extrusion (ECAE). Moreover, the strain-rate reverse dependency of the elongation was found in the ECAE processed Mg-AI system alloy (AZ31) by the achievement of grain refinement and texture control, and improvement in no less than 50% elongation was attained under an impact strain-rate of 1.8 x 10^3 s^<-1> at room temperature. Moreover, it was shown clearly that low temperature or high-strain-rate superplasticity could be discovered in various alloys.(3)In "the establishment of the diffusion bonding and the friction stir welding technology", the equation describes the diffusion bonding condition was drawn from the cavity-disappearance model in the compressive superplastic deformation, and it was shown that the bonding strength of AZ31 alloy sufficient in one third of the bonding time of aluminum under an optimal condition could be obtained. Moreover, although, as for pure magnesium, sufficient bonding strength was not obtained in friction stir welding, with the alloy, 90% or more of the bonding strength of mother material was obtained.(4)In "the establishment of the press fabrication technology from rolling sheets", it was found that the forming limit depended on the fracture limit of the tensile bending on the punch shoulder, and it improved by heating at 473 K or less. Moreover, it was shown that the local deformability, which was hard to evaluate by the tensile test, was important to obtain the good press fabrication, and the new method to evaluate the formability by a notched-specimen bending test was proposed. Less

本研究的目的是通过从电子或原子水平到宏观水平的多尺度控制来实现高性能镁合金的开发。结果总结如下。(1)In“变形行为分析与合金设计的第一性原理分子动力学计算”一文中，通过对镁单晶理想滑移变形时广义层错能的理论计算结果，讨论了导致镁脆性的基滑移面与棱柱滑移面临界分解剪应力差异较大的原因。结果发现，添加Li、Al或Zn可以使差异变小。此外，从电子密度分布的角度讨论了键合强度的各向异性。(2)In“用于具有优异的机械性能和可成形性的合金的材料的构造方法”， ...更多信息 等通道转角挤压（ECAE）可使细小Zr析出相均匀分布，细化晶粒。此外，通过实现晶粒细化和织构控制，在ECAE处理的Mg-Al系合金（AZ 31）中发现伸长率的应变速率反向依赖性，并且在室温下在1.8 × 10^3 s-1的冲击应变速率下获得不小于50%伸长率的改善<-1>。此外，还清楚地表明，在各种合金中都可以发现低温或高应变速率的超塑性。(3)In在“扩散连接与搅拌摩擦焊工艺的建立”的基础上，从压缩超塑性变形的空洞消失模型出发，推导出描述扩散连接条件的方程，并指出在最佳条件下，AZ 31镁合金只需1/3的连接时间就可获得足够的连接强度。此外，虽然对于纯镁，在摩擦搅拌焊接中没有获得足够的接合强度，但是对于该合金，获得了母材的90%以上的接合强度。(4)In在“轧制板材冲压成形技术的建立”中，发现成形极限取决于凸肩拉伸弯曲的断裂极限，并通过在473 K或更低温度下加热来改善。此外，还表明，难以通过拉伸试验评估的局部变形能力对于获得良好的冲压成形是重要的，提出了用缺口试样弯曲试验评价成形性的新方法。少

项目成果

H.Watanabe: "Grain Size Control of Commercial Wrought Mg-Al-An Alloys Utilizing Dynamic Recrystallization"Materials Transactions. 42-7. 1200-1205 (2001)

H.Watanabe：“利用动态再结晶控制商用变形 Mg-Al-An 合金的晶粒尺寸”材料交易。

H.Somekawa: "Diffusion bonding in superplastic magnesium alloys"Materials Science and Engineering. A339. 328-333 (2003)

H.Somekawa：“超塑性镁合金中的扩散接合”材料科学与工程。

S.W.Chung: "Superplastic Deformation Behavior in the Commercial AZ61 Mg Alloy during Biaxial Gas-pressure Forming"Materials Science Forum. 419-422. 539-544 (2003)

S.W.Chung：“商业 AZ61 镁合金在双轴气压成形过程中的超塑性变形行为”材料科学论坛。

H.Watanabe: "Workability Utilizing Superplastic Flow in Magnesium-Based Materials"Kagakuto Kogyo. 74-5. 227-233 (2000)

H.Watanabe：“在镁基材料中利用超塑性流动的可加工性”Kagakuto Kogyo。

H.Watanabe: "Observation of high-strain-rate superplasticity in ZK60 and SiCp/ZK60 composite"Materials Science Forum. 304-306. 297-302 (1999)

H.Watanabe：“ZK60 和 SiCp/ZK60 复合材料中高应变率超塑性的观察”材料科学论坛。