( 1. 哈爾濱工業(yè)大學(xué) 現(xiàn)代焊接生產(chǎn)技術(shù)國(guó)家重點(diǎn)實(shí)驗(yàn)室，
哈爾濱 150001;
2. 深圳市億鋮達(dá)工業(yè)有限公司， 深圳 518101)
摘 要: Sn-Ag-Cu系合金是最有可能替代Sn-Pb釬料的無(wú)鉛釬料。 介紹了一種測(cè)量其力學(xué)性能的新方法， 即通過(guò)微壓痕儀精確測(cè)量不同加載速率下壓子的壓入深度h與加載載荷F的關(guān)系來(lái)確定釬料的彈性模量E和蠕變速率敏感指數(shù)m。 結(jié)果表明： 加載速率對(duì)釬料蠕變壓痕F-h曲線和壓入深度有著重要的影響； Oliver-Pharr方法確定的釬料彈性模量取決于卸載過(guò)程而與加載速率無(wú)關(guān)。 基于壓痕做功概念定義了壓痕蠕變硬度和蠕變應(yīng)變速率， 從而給出釬料的蠕變速率敏感指數(shù)。 Sn-3.5Ag-0.75Cu與Sn-3.0Ag-0.5Cu釬料蠕變壓痕測(cè)試表明合金成分影響Sn-Ag-Cu系無(wú)鉛釬料的力學(xué)性能。
關(guān)鍵字: 無(wú)鉛釬料； 微壓痕； 彈性模量； 蠕變速率敏感指數(shù)；Sn-Ag-Cu系
using micro-indentation
（ 1. State Key Laboratory of Advanced Welding Production Technology, Harbin Institute of Technology, Harbin 150001, China;
2. Yik Shing Tat Industrial Co., Ltd., Shenzhen 518101, China）
Abstract: Sn-Ag-Cu series alloy is considered as the lead-free alternative to lead-tin alloys. A new method was introduced to measure the mechanical properties, i.e. modulus of elasticity and creep strain rate sensitivity by using depth-sensing micro-indentation with the influence of loading rates on load—displacement (F-h) relationship. The resulting indentation F-h curves are loading-rate-dependent and have varying creep penetration depths during the same hold time. The derived modulus of elasticity values with Oliver-Pharr method from unloading curves are loading rate-independent. The creep strain rate sensitivity can be determined from the relationship between the creep hardness and creep strain rate by the definition of “work of indentation”. Also, micro-indentation tests on two Sn-3.5Ag-0.75Cu and Sn-3.0Ag-0.5Cu lead-free solder alloys show a slight influence of alloy composition on mechanical properties for Sn-Ag-Cu series solder.
Key words: lead-free solder; micro-indentation; modulus of elasticity; creep strain rate sensitivity; Sn-Ag-Cu series
