Papers by Author: Dennis Hahmann

Abstract: Steel-ceramic-composites offer a high potential as protective layers of mechanically and abrasively high loaded machine parts. The machining of steel-ceramic-composites is a high challenge for the process design due to the very different material properties of the brittle ceramic particles, embedded in the ductile steel matrix. Both materials have to be machined in ductile mode simultaneously to gain high surface qualities. Thus, the material separation mechanisms have to be understood for an adequate process design. In this paper, a new process characteristic is introduced that describes the influence of the grinding process settings on the process forces and workpiece surface roughness in grinding steel-ceramic-composites.

Abstract: Harder workpiece materials and increased efficiency requirements for grinding processes make the use of super abrasive grinding wheels indispensable. This paper presents newly developed processes for the dressing of super abrasive grinding wheels. The different bond systems of grinding wheels require distinct dressing process. In this paper, dressing processes for metal and vitrified bonded grinding wheels are investigated. It introduces the method of electro contact discharge dressing for the conditioning of metal-bonded, fine-grained multilayer grinding wheels. A description of the essential correlation between dressing parameters and the material removal rate of the bond material is presented. The considered parameters are the dressing voltage, the limitation of the dressing current and the feed as well as the infeed of the electrode. For the grinding of functional microgroove structures, multiroof profiles with microscopic tip geometries are dressed onto the grinding wheel. For this, a profile roller in combination with a special shifting strategy is applied on finegrained vitrified bonded grinding wheels.