采用过冷液体等温处理的方法制备出直径为3 mm的Cu45Zr42Al8Ag5合金圆棒,研究了过冷液体等温处理对铜基内生复合材料的热稳定性和力学性能的影响,研究表明,过冷处理后的试样均为原位自生晶体/非晶复合材料,且具有较好的热稳定性。由铜基非晶合金压缩后的应力-应变曲线可以看出,随保温时间的延长,最大抗压强度逐渐降低,最大为2266 MPa;而塑性变形量逐渐增大,最大为1.46%,相比于过热处理的试样,过冷处理的试样的力学性能比较好。断口微观形貌分析表明,吸铸温度为1090 K保温时间为6 min的试样断口呈现明显的脉络状纹络,使得铜基非晶具有较大的抗压断裂强度和较好的塑性。
A series of Cu45Zr42Al8Ag5 amorphous rods with 3 mm in diameter were prepared by isothermal treatment in supercooled liquid.The effect of isothermal treatment in supercooled liquid on the thermal stability and mechanical properties of Cu-based bulk metallic glasses were studied.The results showed that the samples were composites containing in situ crystalline after supercooling treatment,and exhibited an excellent thermal stability.From the compressive stress-elongation curves of Cu45Zr42Al8Ag5 BMG alloys,the compressive fracture strength gradually decreased with the increase of holding time,as the compressive plastic strain increased.And the best compressive strength and plastic strain were 2266 MPa and 1.46%,respectively.Compared to the samples fabricated by overheating treatment,samples prepared by supercooling treatment exhibited better mechanical properties.The fracture surface of the sample treated at 1090 K for 6 min showed obviously vein-like patterns,which was contributed to the high compressive fracture strength of Cu-based bulk amorphous alloys.