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2014 №12 (02) DOI of Article
10.15407/tpwj2014.12.03
2014 №12 (04)

The Paton Welding Journal 2014 #12
The Paton Welding Journal, 2014, #12, 11-14 pages  

Effect of temperature of thermomechanical treatment on quality of dissimilar metal joints

L.Yu. Demidenko, N.A. Onatskaya And V.D. Polovinka


Institute of Pulse Processes and Technologies, NASU. 43a Oktyabrsky Ave., 54018, Nikolaev, Ukraine. E-mail:iipt@iipt.com.ua
 
 
Abstract
At present time, pressure welding methods acquire more and more distribution for quality joining of dissimilar metals. The Institute of Pulse Processes and Technologies of the NAS of Ukraine has developed a new method of welding of materials in solid state using current pulses. In essence, it lies in the fact that metals being welded at ambient temperature are pressure contracted and specific amount of current pulses of amplitude density not less than 1.2x109 A/m2 and duration not less than 2x10-4 s are passed through deformation zone for intensification of plastic deformation at stage of physical contact formation. At that mutual deformation of surface projection provides for sufficiently tight contact of surfaces being welded and allows for their isolating from ambient environment. A welded joint is formed at further heating by type of diffusion one without application of special shield of the surfaces from oxidation. Aim of present work is an investigation of effect of temperature of thermomechanical treatment on quality of joints in welding of dissimilar metals in solid state using current pulses of large density. Such research methods as mechanical shearing tests, optical metallography and micro X-ray spectral analysis were used at that. It was determined as the result of experiments that 800 °C temperature is the most favorable for providing a quality steel 20 plus copper M1 welded joint, since at that no discontinuities are present in joint zone and clearly expressed initial structure is preserved in metal itself. 9 Ref., 3 Tables, 5 Figures.
 
 
Keywords: welded joints of dissimilar metals, temperature of thermomechanical treatment, current pulses of large density, self-sealing of inter-contact zone, metallographic investigations, mechanical shearing tests
 
 
Received:                05.05.14
Published:               29.12.14
 
 
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