Synthesis and Industrial Trial of Non-Equilibrium Aluminum Alloys with a Combination of High Heat-Resistance, High Strength and Good Workability

为了开发出具有较高室温强度(600 Mpa)、573K高温强度(300 Mpa)、723K下100小时耐热性、高可加工性和高耐磨性的新型高温铝合金，我们合成并研究了多种Al-Ti-Cr-X快速凝固粉末冶金合金及其复合材料的力学性能。因此，我们成功地合成了Al_&lt；92.5&gt；Ti_&lt；2.5&gt；Fe_&lt；2.5&gt；Cr_&lt；2.5&gt；RS粉末冶金合金，达到了本研究的目标。RS粉末冶金合金具有以下力学性能：(1)具有较高的常温拉伸强度；该合金的抗拉强度为600~660 MPa，延伸率为3~4%。(2)该合金具有较高的高温抗拉强度。合金在473K、573K和673K时的抗拉强度分别为480、320和150 MPa。(3)合金具有较高的热稳定性。723K保温100小时和623K保温1000小时的常温强度下降幅度在10%以内。(4)该合金可以在高应变速率下进行热加工，同时保持550 Mpa左右的常温强度。合金在823K的高应变速率下表现出较大的延伸率，伸长率为1 S，室温强度下降15%，5小时。(5)添加2.5%的碳化硅颗粒使复合材料的杨氏模量和高温耐磨性提高到473K。一些公司正在对Al_&lt；92.5&gt；Ti_&lt；2.5&gt；Fe_&lt；2.5&gt；Cr_&lt；的实际应用进行试验。本研究开发了2.5&GT；RS粉末冶金合金。

In order to develop novel elevated-temperature Aluminum alloys having a combination of high ambient-temperature strength of 600 Mpa, high elevated-temperature strength of 300 Mpa at 573 K, high heat resistance for 100 hr at 723 K, high workability and high wear resistance, we synthesized and investigated the mechanical properties of many Al-Ti-Cr-X rapidly solidified powder metallurgy alloys and their composites. Accordingly, we have succeeded in synthesizing Al_<92.5>Ti_<2.5>Fe_<2.5>Cr_<2.5> RS P/M alloy that reached our target of this study. The RS P/M alloy exhibited the following mechanical properties.(1) The alloy exhibited high tensile strength at ambient temperature. The tensile strength was ranging from 600 MPa to 660 MPa and the elongation was 3-4 %.(2) The alloy exhibited high tensile strength at elevated temperature. The tensile strength was 480 MPa, 320 MPa and 150 MPa at 473K, 573K and 673K, respectively.(3) The alloy exhibited high thermal stability. The decrease in ambient-temperature strength due to annealing at 723K for 100 hr and 623K for 1000 hr was within 10 %.(4) The alloy can be hot-worked at high strain-rate with keeping the high ambient-temperature strength of about 550 Mpa. The alloy exhibited a large elongation at high strain-rate of 10^<-1> to 1 s^<-1> at 823 K where the decease in ambient-temperature strength was within 15 % for 5 hr.(5) The composite with 2.5 vol% SiC particles exhibited improved the Young's modulus and the wear resistance at high temperature of 473 K.Some companies are trying tests of practical application of the Al_<92.5>Ti_<2.5>Fe_<2.5>Cr_<2.5> RS P/M alloy developed in this study.