Assessment of geometry characteristics and mechanical resistance properties of spot welds via robust designArticle based on a version presented at the XXXII CONSOLDA, Belo Horizonte, Minas Gerais, Brazil, 2–5 October 2006.

^1.[email protected]

Abstract

The resistance spot welding process is widely used in the automotive industry, because it provides high productivity (over 20 spots per minute) and good quality. However, the introduction of galvanized steels onto production lines has brought difficulties in correctly adjusting welding parameters. This work therefore presents a detailed study of the influence of the principal parameters of the process (upslope time, current time, downslope time, electrode force and water flow) on the geometry and resistance of spot welds on galvanized steel plates. To do this, experimental robust planning was considered (the Taguchi method) for the factors mentioned above, evaluating the robustness of the system (analysis of the reduction of the signal/noise level) in regard to the diameter, indentation and mechanical resistance of the spot weld (responses). The difference between this work and others lies in the fact that instead of maintaining a fixed current level, which is the traditional method, the energy used in the process (current × time) is fixed. The conclusion is that it is possible to obtain robust parameters for a system in which the statistically significant parameter is current time.

Keywords:

• resistance spot welding
• statistical techniques
• robust design

Acknowledgements

We thank Federal University of Uberlândia (UFU) LAPROSOLDA, where this project took place, and its team, professors and students for their help in executing the project.

Notes

^1. [email protected]

^2. [email protected]

^3. [email protected]

Article based on a version presented at the XXXII CONSOLDA, Belo Horizonte, Minas Gerais, Brazil, 2–5 October 2006.

Additional information

Notes on contributors

José Enrique Vargas Aures

1. 1. [email protected]

Sadek Crisostomo Absi Alfaro

2. 2. [email protected]

Oliveira Vilarinho Louriel

3. 3. [email protected]