| 摘要: |
| 采用砂型铸造方法，制备了Mg-11.2Gd-3.5Y-0.46Zr合金，通过正交试验方法优化了合金热处理工艺。结果表明，合金在525℃×10h+240℃×9h热处理工艺下，得到最佳力学性能：抗拉强度σb360MPa、屈服强度σs305MPa，延伸率δ54.0%。背散射电子扫描结果显示，嵌入基体的高稀土含量的Mg-RE中间相存在于铸态、固溶态及时效态，对合金的强化作用明显；T6状态下，合金的断裂机理以准解理断裂为主。 |
| 关键词: 砂铸Mg-Gd-Y-Zr合金 热处理 正交试验 断裂机制 |
| 基金项目: |
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| Heat Treatment Optimization of Sand Cast Mg-Gd-Y-Zr Alloy |
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Zou Wenbing Hou Zhengquan Li Baohui Xiao Lv Wang Baobing Li Liping Lin Chucheng1, Lin Chucheng2
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1. Shanghai Spaceflight Precision Machinery Institute, Shanghai 201600;2. Shanghai Institute of Ceramics, Shanghai 200050
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| Abstract: |
| In order to optimize the tensile property of Mg-Gd-Y-Zr alloy, Mg-11.2Gd-3.5Y-0.46Zr was prepared for orthogonal experiment. The results showed that the optimal heat treatment was 525℃×10h+240℃×9h, the tensile strength, yield strength and elongation was 360Mpa, 305Mpa, 4% respectively. SEM fracture observation results suggested that the second-phase precipitates, which were Mg-RE intermediate phase, existed in as-cast (F), solution-treated (T4) and artificially-aged (T6) conditions. In optimal T6 condition, the fracture mechanism was mainly cleavage fracture. |
| Key words: sand-casting Mg-Gd-Y-Zr alloy heat treatment orthogonal experiment fracture mechanism |
