摘要
采用喷射沉积工艺制备了快速凝固AlFeVSi合金圆锭坯.从锭坯上截取试样,采用模压工艺进行了高温(450和500℃)致密化.通过金相显微组织观察、透射电镜分析、扫描电镜分析、力学性能检测等手段,研究了在高温模压过程中的应力应变状态和金属流变规律对喷射沉积AlFeVSi合金坯的致密化过程与组织性能的影响,并采用铝包套高温(450℃)模锻工艺经将喷射沉积Al 9 20Fe 1 37V 2 30Si合金压实坯加工成完全致密化的模锻件.结果表明,高温模压可以明显提高沉积坯的致密度,但在有限的高向加载应力条件下难以使沉积坯达到理想的结合状态,与喷射沉积坯相比,虽然模压制品强度和塑性有明显提高,但仍处于低水平.喷射沉积坯经热压后,采用铝包套模锻成形,可以实现锻坯有效致密化和改善粉末间结合状态,明显提高材料屈服强度、抗拉强度和延伸率.喷射沉积Al 9 20Fe 1 37V 2 30Si合金直径=200mm铝包套模锻件拉伸力学性能(σ0 2、σb和δ)可达如下指标:室温(25℃),411MPa、463MPa、9 7%,高温(350℃),180MPa、190MPa、8 9%.
Columnar blanks of rapidly solidified AlFeVSi heat-resistant aluminum alloy were prepared by using spray deposition technique. The spray deposited specimens, cut from the columnar blanks, were compacted at 450 and 500℃ by means of die-press process. Influence of stress-strain distribution and metal flow character in the pressing billet on compacting process, microstructures and mechanica properties of spray deposited blank of AlFeVSi aluminum alloy was studied by means of optical microscopy, transmission electron microscopy, scanning electron microscopy and measure of tensile properties. In addition, the hot-compacted blanks of spray deposited Al-9.20Fe-1.37V-2.30Si aluminum alloy were fabricated into full dense die-forged pieces through aluminum package die-forging process at high temperature of 450℃. The results show that, spray deposited AlFeVSi alloy blanks can be compacted obviously through high temperature die-press process. However, it is difficult to realize good metallurgical binding state in the condition of limited loading stress along highness direction. Tensile strength and plasticity of the die-compacted produces are improved obviously in comparison with those of the spray deposited blank, but they are still at the lever of lower performance. The forged pieces, produced through aluminum package die-forging process after hot-pressing of the spray deposited blanks of AlFeVSi alloy, can get to effectual densification degree and excellent metallurgical binding and the yield strength,tensile strenth and ductieity of the material can be improved obviously. Therefore, the diameter=200 mm forge pieces, prepared by using two-stage large-deformation aluminum package die-forging process, have good tensile properties of σ_0.2=411 MPa, σ_b=463 MPa and δ=9.7% at room temperature, and σ_0.2=180 MPa, σ_b=190 MPa and δ=8.9% at high temperature of 350℃.
出处
《材料与冶金学报》
CAS
2004年第3期213-218,共6页
Journal of Materials and Metallurgy
基金
国家重点基础研究发展规划项目(G1999064900).
关键词
喷射沉积
耐热铝合金
显微组织
力学性能
spray deposition
heat-resistant aluminum alloy
microstructure
mechanical properties
