Work

Study On the Reliability of Lead-Free Solder Joint Assemblies Under Combined Effects of Vibrations and Extended High-Temperature Exposure

Year: 2026

Type: article

Abstract: The solder joint represents one of the weakest links within electronic assemblies, especially for automotive systems such as engine control units, variable valve sensors, and crankshaft-camshaft sensors. These base components often face harsh environments in day-to-day activities, including temperatures as high as 150 °C, coupled with vibration, shock, and strain rates ranging from 1 to 100 times per second. These negative effects resulting from prolonged exposure to high temperatures are motivating researchers to incorporate various dopant additives into SnAgCu (SAC) solders. Understanding the mechanical properties of such lead-free solders will be crucial for ensuring reliability and longevity in extreme electronic packages under high-temperature and high-strain-rate environmental conditions. The combination of all these vibrations and high temperatures can significantly accelerate the degradation of electronic components. Most existing research on solder joints has been conducted either on vibrational stresses at room temperature or on thermal cycling, primarily for traditional and unaged solders such as SAC105 and SAC305. Most studies performed using FE analysis to date have considered only the linear-elastic behavior of solder materials. Energy-based life prediction models of PCB-package assemblies under new doped solders are not available. In this work, novel SAC-Q doped solder is under study for preparing and testing PCB-package assemblies under various conditions, such as ambient temperatures up to 150 °C and harmonic vibration loads, 5 g and 10 g. The first natural frequencies of the test boards were measured using both experimental and finite element analysis (FEA)-based modal analysis, while 2D DIC was employed to extract displacement data. Weibull distribution analysis was performed to extract the characteristic lives under various test conditions, including different temperatures and vibration loads. A damage model has been developed for predicting the life and reliability of electronic assemblies under high-temperature vibration. The damage model can be used to assess the effect of accumulated finite element plastic work on the expected cyclic life under aging conditions, including aging temperature, aging time, and operating temperature. The damage model has been validated with experimental data. FEA was conducted to simulate the harmonic vibration loading of the PCB-package assemblies, considering the viscoplastic behavior of solder joints using previously extracted Anand model constants. Extracted hysteresis stress–strain curves and accumulated plastic work densities were used in developing an energy-based life prediction model that can predict the characteristic life of unaged and thermally aged PCB-package assemblies under different test conditions.

Source: Journal of Electronic Packaging

DOI: 10.1115/1.4071140

Authors: Pradeep Lall, Vishal Mehta, Jeff Suhling, Ken Blecker

Institutions: Auburn University, United States Army Combat Capabilities Development Command, U.S. Army Combat Capabilities Development Command Armaments Center

Language: English

Topic: Electronic Packaging and Soldering Technologies

Subfield: Electrical and Electronic Engineering

Field: Engineering

Domain: Physical Sciences

Open Access status: hybrid

Funder: Auburn University

OpenAlex ID: W7129221916