Diffusion bonding of fine grained high carbon steels in the super-plasticity temperature range

摘要

In this study, diffusion bonding behaviour of two high carbon hypocutectoid steels was investigated. The steel specimens were heat treated to induce a fine grain structure and diffusion bonded within a temperature range where these steels exhibit superplasticity. The results showed that these steels could be bonded successfully at 650 deg C and 735 deg C within the supcrplastic temperature range, but poor diffusion bonds were fabricated at a temperature of 850 deg C. The poor bonding was attributed to an increase in grain size, which not only reduce grain boundary diffusion mechanisms, but also a loss in superplaslic deformation behaviour could be expected.