Deposition welding of hot forging dies using nanoparticle reinforced weld metal

Abstract

In the application field of forging, the form-giving tool components are subject to process-related severe environmental conditions, such as high mechanical loads acting simultaneously with high tribological and thermal charges. Due to high machine hour rates as well as increasing environmental requirements in terms of energy consumption, wear protection methods and suitable repair measures for forging tools become more and more important. Laser deposition welding represents an established process for the repair of complex shaped surfaces. A new approach is the addition of nano-sized ceramic particles to improve the mechanical properties. The main idea is to reduce the grain size of the cladded layers by adding nano-sized nuclei. A fine grained microstructure will improve strength as well as ductility and fatigue resistance. Furthermore small hard particles can improve the wear resistance without affecting the friction of the surface. After the cladding process the surface has to be finished usually by turning, milling and grinding operations. Within the presented paper the potential of nanoparticle-reinforced deposition welding with regard to increasing the wear resistance of forging dies will be examined. First, the process of nanoparticle-reinforced deposition welding will be presented. Afterwards it will be shown that yttrium oxide, titanium carbide and tungsten carbide nanoparticles in an AISI H10 matrix material will influence the friction coefficient between forging tool and material as well as the wear properties

Application of design of experiments to forging simulations to increase die life expectancy

“…To this end, besides the classical nitriding treatment, special coatings and die processing techniques are being investigated [24]. For example, Behrens et al [25] added a layer of nano-sized ceramic particles to a fine-grained microstructure to increase strength, ductility, fatigue and wear resistance without affecting surface friction. Gronostajski et al [12,15] also tested different types of surface coatings in order to assess, also with the use of 3D scanner and hardness tests, which of them showed the best behaviour against damage mechanisms.…”