Skip to Main content Skip to Navigation
Theses

Fiabilité mécanique des assemblages électroniques utilisant des alliages du type SnAgCu

Abstract : Since the use of the lead was restricted in electronic assemblies, the electronic market turned on lead-free alloys for electronic assemblies. Most of electronic manufacturers chose SnAgCu (SAC) to replace SnPb alloys. For SAC, former results suggest that high temperature thermal ageing causes a significant drop in mechanical properties, which stabilises after several years at room temperature. The aim of this work is to analyse the impact of thermal ageing on the fatigue damage of SAC305 electronic assemblies under mechanical loadings.This study first focused on the mechanical behaviour of SAC305 alloy. Then, the fatigue damage of SAC305 was analysed on solder joints.The impact of thermal ageing on the mechanical behaviour of SAC305 was evaluated at the bulk scale and at the solder joint scale. Changes in the hardness and in the cyclic mechanical behaviour at room temperature were linked to a grain growth phenomenon. Compression tests on SAC305 solder balls, which are representative of real structure, showed the same changes in the mechanical behaviour. Two viscoplastic constitutive models of mechanical behaviour were identified at the solder joint scale for both initial and aged conditions. Numerical simulations were carried out using these models and led to the validation of the proposed approach.The impact of thermal ageing on the fatigue damage of SAC305 alloy was evaluated thanks to torsion tests on assembled boards. The results of these tests show that the thermal ageing decreases the number of cycles to failure in low cycle fatigue. This observation is very important considering the reliability risk for electronic devices
Document type :
Theses
Complete list of metadatas

https://tel.archives-ouvertes.fr/tel-00604954
Contributor : Abes Star :  Contact
Submitted on : Thursday, June 30, 2011 - 10:38:28 AM
Last modification on : Tuesday, November 24, 2020 - 2:18:04 PM
Long-term archiving on: : Saturday, October 1, 2011 - 2:21:46 AM

File

Dompierre_Benoit_DLE.pdf
Version validated by the jury (STAR)

Identifiers

  • HAL Id : tel-00604954, version 1

Collections

Citation

Benoît Dompierre. Fiabilité mécanique des assemblages électroniques utilisant des alliages du type SnAgCu. Autre. Ecole Centrale de Lille, 2011. Français. ⟨NNT : 2011ECLI0001⟩. ⟨tel-00604954⟩

Share

Metrics

Record views

1026

Files downloads

13561