Feinstkornhartmetalle zum Bohren und Fräsen

FKM 1998
Booklet No. 234
Project No. 205

Abstract:

The development of ultra-fine and ultrafine-grained carbides has made it possible to significantly increase the hardness and bending strength compared to carbides with conventional grain sizes. This fulfills important requirements for use as a cutting material for solid carbide tools for drilling and milling. There are only insufficient recommendations for the use of these cutting materials on steel tools. The aim of this project was to investigate the application behavior of fine-grain carbide tools in the machining of steel materials. When drilling steel materials, it was demonstrated that the use of ultra-fine and ultra-fine grain carbide tools with cooling lubricant can significantly increase tool life compared to carbide tools with conventional grain sizes. In addition, the higher bending strength means that the feed rate in particular can be increased, which means that the process performance can be increased by correspondingly high cutting parameters in areas that lead to the failure of tools made of carbide with a conventional grain size. The use of an internal lubricoolant supply leads to a further increase in tool life for ultra-fine grain carbides and ensures that the machining forces remain almost constant even with increasing wear. This is an important prerequisite for stable machining processes. An important finding of the milling tests with MWF is that uncoated tools made of carbide with a conventional grain size have proven to be more wear-resistant than corresponding tools made of fine-grain carbide. The properties of high hardness and high bending strength of fine-grain carbides cannot be realized in the process due to the comparatively low hot hardness. Tool wear can be significantly reduced by using carbide-coated milling tools made from fine-grain carbide. The high wear resistance of carbide-coated fine-grain carbide milling cutters allows an increase in feed rate without an increase in wear. In addition, machining is also possible without cooling lubricant, as tool wear increases only slightly in dry cutting. Coated milling tools made of fine-grain carbide are characterized by a higher wear resistance than carbides of conventional grain size. As the achievable surface quality deteriorates with increasing tool wear, the use of wear-resistant coated fine-grain carbide milling cutters offers advantages in terms of component quality. Scope of report:
94 p., 63 ill., 68 lit. Start of work:
01.07.95 End of work:
31.12.97 Funding body:
FKM I AiF-No. 10283 Research center:
Institute of Production Engineering and Machine Tools University of Hanover Head of Institute:
Prof. Dr.-lng. Dr.-lng. E.h. H. K. Tönshoff Processor and author Dr.-lng. B. Karpuschewski Dipl. -lng. C. Arendt Chairman of the expert group:
R. Ankenbrand, Flender AG, Bocholt Chairman of the Advisory Board:
Prof. Dr.-lng. H. Kipphan Heidelberger Druckmaschinen AG, Heidelberg