Thermal Fatigue of Solder Joints

焊点的热疲劳

• 批准号: 0140605
• 负责人: Mark Palmer
• 金额: --
• 依托单位: Kettering University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-07-01 至 2004-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0140605&HistoricalAwards=false
• 关键词: Thermal; Fatigue; Solder; Joints

Funding is provided under this RUI award to permit 8 teams of undergraduatestudents over the course of a two-year period to participate in a continuousresearch project evaluating the thermomechanical fatigue of solder joints. Tomake this experience successful it is proposed to create a unique learningexperience which is a combination of innovative classroom instruction andresearch. A master's student will assist in this project, and by doing so have aunique master's level experience designed to require the evaluation of the workof others, the synthesis of their work with that of the undergraduates and thedevelopment of leadership skills. There are research and teaching components tothis proposed project.Research: Thermomechanical fatigue (TMF) is the leading cause of solder jointfailure in electronic assemblies. TMF of solder joints is difficult to model asthere are many complex and interacting factors effecting the progression ofdamage to the joint. Because of the high homologous temperatures (0.8 or higher)significant microstructural evolution occurs during TMF, changing the propertiesof the material as TMF progresses. An experimentalinvestigation will be conducted to 1) identify those more readily measured materialproperties most likely to affect TMF resistance, 2) evaluate the variousacceleration factors used in TMF testing, and 3) evaluate the role of wetting inTMF failures.As a result of this research much insight into TMF failure will be gained - 1)progress will be made toward the development of an experimentally verifiedenergy model, and 2) the role of wetting in adhesion will be assessed. Thismeans that those considering using lead-free solder alloys will be able to usediagnostic "tools" not currently available -- the combination of materialproperties which correlate to TMF resistance.Teaching: To enable undergraduates to participate in a continuing researchprogram, a unique "classroom" experience will supplement the research. Theseclass sessions will embrace interactive learning techniques, and expose theundergraduates to 1) the necessary theoretical background, 2) the status of theproject, 3) necessary lab techniques including statistical analysis, 4) oral andwritten communication skills, and 5) broader issues including ethics andeconomic impact. All of these subjects will be context based. The philosophy ofthis course is that upper level undergraduates need to perform at the synthesislevel of Bloom's Taxonomy, and their experience is designed to enable them to doso.The master's student will be required to perform at the evaluation level ofBloom's Taxonomy (evaluating the work of the undergraduates) and synthesize thiswork with their own study on wetting, thus participating in a unique integratingexperience. Additionally the student will develop leadership skills, andpossibly be persuaded to pursue a doctoral degree and develop a desire to teach.The master's students experience may also encourage the undergraduates to pursuea graduate degree.It is felt that this comprehensive plan will maximize the chances for successand serve as a demonstration project for others desiring to incorporate researchinto the undergraduate experience and developing a novel masters program.Impact: It is felt that this program can significantly impact undergraduateeducation by serving as a proof of concept in the development of researchoriented courses, generating an appreciation of life-long learning, anddemonstrating the value of undergraduate research to the outside community. Thiswork complements the current work of the PI and lays the foundation for hisfuture plans.

该 RUI 奖项提供资金，允许 8 个本科生团队在两年的时间内参与评估焊点热机械疲劳的连续研究项目。为了使这种体验取得成功，建议创造一种独特的学习体验，将创新的课堂教学和研究相结合。硕士生将协助该项目，并通过这样做获得独特的硕士水平经验，旨在要求评估他人的工作、将他们的工作与本科生的工作相结合以及领导技能的发展。该拟议项目包含研究和教学部分。研究：热机械疲劳（TMF）是电子组件中焊点失效的主要原因。焊点的 TMF 很难建模，因为有许多复杂且相互作用的因素影响焊点损坏的进展。由于同源温度较高（0.8 或更高），TMF 过程中会发生显着的微观结构演化，随着 TMF 的进行，材料的性能也会发生变化。将进行实验研究，以 1) 识别那些更容易测量的最有可能影响 TMF 电阻的材料特性，2) 评估 TMF 测试中使用的各种加速因素，以及 3) 评估润湿在 TMF 失效中的作用。这项研究的结果将获得对 TMF 失效的深入了解 - 1) 将在开发经过实验验证的能量模型方面取得进展，2) 润湿的作用 将评估粘附力。这意味着那些考虑使用无铅焊料合金的人将能够使用目前尚不可用的诊断“工具”——与TMF电阻相关的材料特性的组合。 教学：为了使本科生能够参与持续的研究项目，独特的“课堂”体验将补充研究。这些课程将包括互动学习技巧，并向本科生展示1）必要的理论背景，2）项目的现状，3）必要的实验室技术，包括统计分析，4）口头和书面沟通技巧，以及5）更广泛的问题，包括道德和经济影响。所有这些主题都将基于上下文。本课程的理念是，高年级本科生需要在布鲁姆分类学的综合水平上进行表演，他们的经验旨在使他们能够做到这一点。硕士生将被要求在布鲁姆分类学的评估水平上进行表演（评估本科生的工作），并将这项工作与他们自己的润湿研究综合起来，从而参与独特的整合体验。此外，学生将培养领导技能，并可能被说服攻读博士学位并培养教学愿望。硕士生的经历也可能会鼓励本科生攻读研究生学位。人们认为，这一全面的计划将最大限度地提高成功的机会，并为其他希望将研究纳入本科生经历并开发新颖的硕士课程的人提供示范项目。影响：人们认为该计划可以显着影响 通过作为研究型课程开发的概念验证、产生对终身学习的欣赏并向外界展示本科生研究的价值来促进本科生教育。这项工作补充了 PI 当前的工作，并为其未来的计划奠定了基础。