MOSCOW, April 4. /TASS/. A group of researchers from the Siberian Federal University (the SFU) headed by Galina Zeyer, dean of Material Science and Materials Processing Technology department, came up with a new method of diffused welding under high pressure with the use of a layer of a special material. The invention could be used for heterogeneous materials welding in various fields of engineering, the SFU says.
“This method does not require special equipment and is economically advantageous for the production of items which demand diffused welding”, - the press release says.
Diffused welding is a connection of two homogeneous or heterogeneous materials under high pressure and temperature range of 0.4-0.8 of melting temperature of more fusible material in the mixture. In this newly-elaborated method, the SFU researchers propose to add an interlaminar layer facilitating the connection of materials. A suspension of nickel powder and a liquid binder, polyvinyl butyral solution, can act as such layer.
“Interlaminar layers assist in decreasing chemical heterogeneity and thermodynamic disequilibrium, excluding the formation of intermetallic compounds (chemical compounds of metals) in the weld junction and significantly reduce deformation impact of high temperature on welded materials and details. Besides, the new method facilitates lowering the temperature of diffused welding,” Zeyer says.
The researchers believe that the new method could assist in getting a durable connection of heterogeneous materials, saving their structure and initial characteristics, and increase the quality of a welded connection due to ensuring a uniform thickness, powder layer density, and lesser residual porosity.