Friction Weldability of Grey Cast Iron

Jeong, Ho-Shin; Bang, Kook-Soo

doi:2014.32.3.309

J Weld Join > Volume 32(3); 2014 > Article

Research Paper

Journal of Welding and Joining 2014;32(3):309-315.
DOI: https://doi.org/10.5781/JWJ.2014.32.3.95 Published online June 30, 2014.

Friction Weldability of Grey Cast Iron

Ho-Shin Jeong^*,†, Kook-Soo Bang^**

Correspondence: Ho-Shin Jeong,
Email: hsjeong@pknu.ac.kr

Abstract

Joining of grey cast iron by fusion welding has much difficulties for its extremely low ductility and low toughness because of the flake form of the graphite. And the brittle microstructure, i.e. ledeburite may be formed during fusion welding by its rapid cooling rates. By these kinds of welding problem, preheat and post heat treatment temperature must be increased to avoid weld crack or welding problems. In order to avoid these fusion welding problem, friction welding of cast iron was carried out for improving joint soundness, establishing friction welding variables. There is no factor for evaluating friction weldability in continuous drive type friction welding. In this point of view,this study proposed the parameters for calculating friction weld heat input. The results obtained are as follows ; 1. There was a close relationship between tensile strength and flash appearance of friction welded joint. 2. Tensile strength was decreased and flash was severely oxidized as increasing frictional heating time. 3. As increased forging pressure P2, flash had a large crack and tensile strength was decreased. 4. As powdered graphite by rotational frictional force induced flat surface and hindered plastic flow of metal ,tensile strength of welded joint was decreased. 5. Heat input for continuous drive type friction welding could be calculated by the factors of P1, P2 and upset distance(δ).

Key Words: Grey cast iron, Friction welding, Friction pressure, Friction heating time, Upse