- 學位論文
電子連接器端子之應力鬆弛現象研究與可靠度評估
Investigation of Stress Relaxation Behavior and Reliability Assessment of Electronic-Connector Pins
摘要
在現今社會眾多的電子用品中，連接器為不可缺少的產品，其高可靠度也成各大廠商所重視的一個環節。提升連接器可靠度之首要工作在找出其主要失效機制，進而探討失效因素及其對連接器壽命與可靠度之影響。根據業界相關經驗，端子之應力鬆弛為連接器失效主要原因之一。有鑑於此，本研究以某廠商生產的2-mm Hard Metric Connector為例，觀察並整理前人針對該型端子應力鬆弛現象所作之實驗結果，透過黏彈力學與可靠度工程等相關理論，評估連接器端子壽命與可靠度。本研究分為兩部分，第一部分為應力鬆弛分析與壽命評估，主要以迴歸方式了解並描述該型連接器端子正向力下降之平均趨勢，再根據業界所訂定之失效準則，探討連接器端子於嚴苛環境下之壽命，而後透過加速模型的運用，反求端子於正常環境下之壽命。由於各端子之應力鬆弛情況不一，因此本研究第二部分即探討該型連接器端子於參數不確定下之可靠度。應用可靠度工程之相關理論，可求得連接器端子於嚴苛環境下之可靠度指標；最後再透過加速模型的運用，評估連接器端子於正常環境下之可靠度指標。由於操作環境之溫度並不一定，本研究將正常環境溫度設定為30 ℃、40 ℃與50 ℃三種。綜合各項分析結果得知，溫度對於連接器端子之應力鬆弛現象有極大影響，因此，選用適合的材料並於適當的溫度下操作，才能確保連接器及其端子之高可靠度。
並列摘要
Electronic connectors are indispensable products in modern society. In order to improve the reliability of electronic connectors, the major failure mechanisms of connectors have to be found and how they affect the life and reliability of connectors have to be studied. Based on experience of manufacturers, the stress relaxation behavior of connector pins is one of the major failure mechanisms of the connector. Therefore, a two-mm hard metric connector is taken as an example. The stress relaxation behavior of connector pins and its relation to life and reliability of the connectors are studied in detail in the present study. The study is divided into two parts. The first part is to find relaxation of the pin’s contact force in an average sense. Based on a certain failure criterion, the life of pins when used in harsh environments can be found. The life of pins when used in normal environments can be evaluated as well through an accelerated model. The second part of the study is to find relaxation of normal force by considering all connector pins as a population and each pin as a sample individual. Uncertainties of several parameters in the force relaxation model are taken into consideration. Reliability theories are applied to find the reliability indexes of connector pins when they are used in harsh environments. The reliability indexes of pins when they are used in normal environments can be evaluated as well through an accelerated model. The normal environments include conditions of 30 ℃, 40 ℃and 50 ℃. The result indicates that temperature does make a great influence on the force relaxation behavior of connector pins as well as their life and reliability. Choosing appropriate material that has better relaxation behavior and letting connectors be operated at appropriate temperatures will improve the reliability of connectors.