To obtain suitable process conditions for diffusion bonding of two types of steel, Hot-Pressure bonding and Hot-Roll bonding techniques are studied.
High carbon steel and low carbon steel are bonded by Hot-Pressure bonding and Hot-Roll bonding with Auto-vacuum Cleaning process. GTAW welding method was employed to seal the bonding surface in Hot-Pressure bonding and SMAW welding was employed in Hot-Roll bonding.
The bond strength was increased by the alloying effect of the diffusion of carbon.
In Hot-Pressure bonding, the bond strength was increased with bonding temperature and it was related to bonding time by the following equation.
In (bond strength)= $A ㆍt^{\frac{1}{2}}$+B
In Hot-Roll bonding, the bond strength was related to rolling reduction ratio(R) by the following equation.
bond strength = CㆍR(2-R)
The bonding process variables for obtaining suitable bond strength are summarized and the possible bond mechanisms are discussed.
