It is known that the strength of alloys can be successfully improved by rapid solidification. The paper presents a process where Cu-Cr-Sn-Zn lead frame alloy is produced by rapid solidification and aging. The microcry...It is known that the strength of alloys can be successfully improved by rapid solidification. The paper presents a process where Cu-Cr-Sn-Zn lead frame alloy is produced by rapid solidification and aging. The microcrystalline structure of rapidly solidified Cu-Cr-Sn-Zn alloy is smaller grain structure examined by optical metallography. The effects of aging processes on the microstructure and properties of the lead frame alloy were investigated. Aged at 500℃ for 15 min the fine coherent precipitates Cr distribute in Cu matrix observed by transmission electron microscopy and the properties of hardness and electrical conductivity properties can reach 178HV and 61%IACS, respectively.展开更多
Cu-Cr-Sn-Zn alloys are one of the most popular lead frame alloys due to their high thermal and electrical conductivity as well as high strength. The effects of microstructure and aging processes on hardness and electr...Cu-Cr-Sn-Zn alloys are one of the most popular lead frame alloys due to their high thermal and electrical conductivity as well as high strength. The effects of microstructure and aging processes on hardness and electrical conductivity of Cu-Cr-Sn-Zn alloy were studied. At 450 ℃ aging for 1 h the fine and ordered precipitates Cr are found and are coherent with Cu matrix. Small and fine Cr precipitates make the Cu-Cr-Sn-Zn lead frame alloy possesses higher hardness and conductivity. At 450 ℃ for 3～6 h,the hardness and electrical conductivity can reach 122～106 HV and 68% IACS -70% IACS,respectively. Hardness 113～109 HV and conductivity 66% IACS -69% IACS are available at 500 ℃ aging for 2～3 h.展开更多
研究了固溶时效和快速凝固时效对Cu Cr Sn Zn合金的微观组织、硬度和导电率性能的影响。结果表明,快速凝固态下合金的晶粒比固溶态时的晶粒要细小得多,细晶强化作用显著;合金快速凝固时效后的析出相较固溶时效的析出相更加弥散、稠密,...研究了固溶时效和快速凝固时效对Cu Cr Sn Zn合金的微观组织、硬度和导电率性能的影响。结果表明,快速凝固态下合金的晶粒比固溶态时的晶粒要细小得多,细晶强化作用显著;合金快速凝固时效后的析出相较固溶时效的析出相更加弥散、稠密,使合金强度得以提高。合金经920℃×1h固溶和500℃×15min时效后,硬度为102HV,导电率达50%IACS;而快速凝固的合金在同样的时效条件下,硬度为179HV,导电率达60%IACS。展开更多
基金supported by the Startup Foundationfor Doctor Scientific Research in Henan University of Sci-ence and Technology (No. 20061009) the Special Fundfor Important Forepart Research in Henan University ofScience and Technology (No. 2008ZD003)the Na-tional Natural Science Foundation of China under grantNo. 50771042.
文摘It is known that the strength of alloys can be successfully improved by rapid solidification. The paper presents a process where Cu-Cr-Sn-Zn lead frame alloy is produced by rapid solidification and aging. The microcrystalline structure of rapidly solidified Cu-Cr-Sn-Zn alloy is smaller grain structure examined by optical metallography. The effects of aging processes on the microstructure and properties of the lead frame alloy were investigated. Aged at 500℃ for 15 min the fine coherent precipitates Cr distribute in Cu matrix observed by transmission electron microscopy and the properties of hardness and electrical conductivity properties can reach 178HV and 61%IACS, respectively.
文摘Cu-Cr-Sn-Zn alloys are one of the most popular lead frame alloys due to their high thermal and electrical conductivity as well as high strength. The effects of microstructure and aging processes on hardness and electrical conductivity of Cu-Cr-Sn-Zn alloy were studied. At 450 ℃ aging for 1 h the fine and ordered precipitates Cr are found and are coherent with Cu matrix. Small and fine Cr precipitates make the Cu-Cr-Sn-Zn lead frame alloy possesses higher hardness and conductivity. At 450 ℃ for 3～6 h,the hardness and electrical conductivity can reach 122～106 HV and 68% IACS -70% IACS,respectively. Hardness 113～109 HV and conductivity 66% IACS -69% IACS are available at 500 ℃ aging for 2～3 h.
文摘研究了固溶时效和快速凝固时效对Cu Cr Sn Zn合金的微观组织、硬度和导电率性能的影响。结果表明,快速凝固态下合金的晶粒比固溶态时的晶粒要细小得多,细晶强化作用显著;合金快速凝固时效后的析出相较固溶时效的析出相更加弥散、稠密,使合金强度得以提高。合金经920℃×1h固溶和500℃×15min时效后,硬度为102HV,导电率达50%IACS;而快速凝固的合金在同样的时效条件下,硬度为179HV,导电率达60%IACS。
