Research on Deformation Control Constitutive Model for Lead Free Electronic Devices

无铅电子器件变形控制本构模型研究

• 批准号: 12650067
• 负责人: SASAKI Katsuhiko
• 金额: $ 0.77万
• 依托单位: HOKKAIDO UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2000
• 资助国家: 日本
• 起止时间: 2000 至 2001
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-12650067/
• 关键词: Electronic Device; Lead Free Solder Alloys; Time Dependent Deformation; Temperature Dependence; Constitutive Modeling; Plastic Deforamtion; Creep Deforamtion; Stress Relaxation; 温度依存性

In this research, for lead free electronic devices, construction of a constitutive model to control deformation of lead free solder alloys was conducted referring to basic tests such as pure tension, creep and stress relaxation. Moreover, a structural analysis using the constitutive model was proposed for the read free electronic devices, and reliability evaluation and structural optimization were carried out. The outlines of the research are as follows :1. Clarification of mechanical and fatigue life characteristic of lead free solder alloys : Basic characteristic of macroscopic mechanical behavior and fatigue failure were observed using the small specimens, which have the diameter of 8mm and are made of 60Sn/40Pb and Sn-3.5Ag-0.75Cu. The tests results showed the characteristic macroscopic inelastic deformation and fatigue life of lead free and lead solder alloys.2. Construction of constitutive model for solder alloys : Considering the results (1) constitutive models adapted to explain the inelastic deformation of lead solder alloys such as 60Sn/40Pb can not used to explain the inelastic deformation of lead free solder alloys, because the viscoplastic deformation of lead solder alloys is much different from that of lead free solder alloys. Then, construction of a new constitutive model to exactly explain the inelastic deformation of the lead free solder alloys was discussed. Since the solder alloys for connecting electronic devices is a few hundreds micro millimeter the internal structural change in solder alloys should be taken into account in the constitutive model. Therefore, the constitutive model based on dislocation density is employed in this research.3. Construction of structural analysis method using the constitutive model: Structural analysis was conducted by incorporate the model into a general purposed program of FEM. The advantage of the constitutive model based on dislocation density was verified.

在本研究中，针对无铅电子器件，参照纯拉伸、蠕变和应力松弛等基本试验，建立了控制无铅焊料合金变形的本构模型。此外，利用本构模型对无读电子器件进行了结构分析，并进行了可靠性评估和结构优化。1.无铅焊料力学性能和疲劳寿命特性的研究：采用直径为8 mm的60Sn/40Pb和Sn-3.5Ag-0.75Cu小试件，观察了无铅焊料的宏观力学行为和疲劳破坏的基本特征。试验结果表明，无铅和含铅焊料合金具有宏观非弹性变形和疲劳寿命的特点。焊料合金本构模型的建立：考虑到以下结果：(1)由于铅焊料合金的粘塑性变形与无铅焊料合金的粘塑性变形有很大的不同，适用于解释60Sn/40Pb等铅焊料合金非弹性变形的本构模型不能解释无铅焊料合金的非弹性变形。在此基础上，建立了能够准确解释无铅焊料合金非弹性变形的新本构模型。由于用于连接电子器件的焊料合金的尺寸为几百微毫米，因此在本构模型中应考虑焊料合金的内部结构变化。因此，本研究采用了基于位错密度的本构模型。利用本构模型构造结构分析方法：将本构模型并入通用有限元程序进行结构分析。验证了基于位错密度的本构模型的优越性。

项目成果

K.Sasaki: "Viscoplastic Deformation of 40Pb/60Sn Solder Alloys-Experiments and Constitutive Modeling"Transactions of ASME, Journal of Electronic Packaging. 123・4. 379-387 (2001)

K.Sasaki：“40Pb/60Sn 焊料合金的粘塑性变形 - 实验和本构建模”，ASME 期刊，电子封装杂志 123・4 (2001)。

K.Sasaki: "Viscoplastic deformation of Sn-3.5Ag-0.75Cu Solder Alloys"Material Science Research International, Special Technical Publication. 2. 397-402 (2001)

K.Sasaki：“Sn-3.5Ag-0.75Cu 焊料合金的粘塑性变形”国际材料科学研究特别技术出版物。

佐々木 克彦: "転位密度を考慮した構成モデルによる二軸ラチェット変形シミュレーション"日本機械学会論文集A編. 68・665. (2002)

Katsuhiko Sasaki：“使用考虑位错密度的本构模型进行双轴棘轮变形模拟”，日本机械工程师学会汇刊，A 版，68, 665。（2002 年）

K.Ohguchi: "Description of Temperature Dependence and Creep Deformation of 60Sn-40Pb Solder Alloys"JSME International Journal Series A. 44・1. 82-88 (2001)

K. Ohguchi：“60Sn-40Pb 焊料合金的温度依赖性和蠕变变形的描述”JSME 国际期刊系列 A. 82-88 (2001)。

K. Sasaki, K. Ohguchi, H. Ishikawa: "Viscoplastic Deformation of 40Pb/60Sn Solder Alloys-Experiments and Constitutive Modeling"Transactions of ASME, Journal of Electronic Packaging. 123-4. 379-387 (2001)

K. Sasaki、K. Ohguchi、H. Ishikawa：“40Pb/60Sn 焊料合金的粘塑性变形 - 实验和本构建模”ASME 汇刊，电子封装杂志。