Cemented tungsten carbides are industrially one of the most used composite materials as
cutting tools, wear parts and replacements of standard materials for tools, dies and machine
components. This work focuses on various aspects of diffusion bonding of tungsten carbide to AISI
304 stainless steel using a Ni-foil interlayer. WC/Ni/AISI 304 combinations were diffusion bonded
at 1000°C using different holding times under argon atmosphere. The microstructure
characterization of the resulting interfaces was carried out by SEM and EPMA. The results show
that successful joining between WC and AISI 304 steel is achieved by the formation of a diffusion
zone at both ends of the Ni foil. All WC/Ni/AISI 304 samples have been joined with no severe
interfacial cracking or porosity at the interface. The joint strength is determined by four-point
bending testing, a maximum of 210 MPa for samples joined at 1000 °C for 60 minutes has been
achieved. These results indicate that there is a strong relationship between the thickness of the
diffusion interface and the mechanical strength of the joints.
Thermal Stress-Based Diffusion Bonding Method: the Case of Oxygen Free Copper to 316L Stainless Steel