Titanium and nickel alloys are mainly used as engineering materials for jet engines in aerospace technology, due to their temperature and oxidation resistance and their small thermal conduction. Cutting of these materials is particular characterised by high mechanical and thermal loads of the cutting wedge. Even by comparably small cutting speeds the tribologic system is dominated by very high wear rates. In addition the chip formation is characterised by snarl chips, which damage the machined surface frequently. The heat can be removed form the tool centre point by a strong cooling beam very fast. Additionally, very warm chips could be hardened, so that they break easily and the machined surface will not damaged. In addition special cooling ... More...


 

One alternative for achieving process cooling using lubricoolant is cryogenic cooling of cutting processes. This holds great potential for further reducing tool temperatures. Cryogenic cooling in machining technology involves the use of media with extremely low temperatures to achieve process cooling. The best-known cryogens are liquid hydrogen (boiling point: 20.268 K = -252.882 °C), liquid nitrogen LN2 (boiling point: 77.35 K = 195.80 °C), liquid oxygen (boiling point: 90.18 K = -182.97 °C) and dry ice/CO2 snow (sublimation point: ... More...


 

The major purpose of the research project is the significant increase of productivity and process stability for milling processes with tools that are equipped with indexable inserts compared to the current state of the art by developing a high pressure coolant supply with a focused coolant jet. For this purpose, the well explored positive influence of high pressure coolant supply on the chip breakage is used among others to develop tools with smaller spiral flutes and as a result, higher numbers of cutting teeth. The productivity in milling of steel and titanium materials with tools that feature multiple rows can be increased by more than 25 % compared to the current state of the art by using tools with higher ... More...


 

The aim of the project ORaKühl is to analyse the influence of high-pressure lubricoolant supply on the surface quality and on the properties of the rim zone of difficult-to-cut materials like titanium and nickel-based alloys. For this purpose, cutting tests are carried out during longitudinal external turning with high-pressure lubricoolant supply using cemented carbide cutting inserts. The conventional 6 bar flood cooling was taken as reference. Beside the reduction of the tool temperature, first results show that high-pressure lubricoolant supply guarantee process stability through an effective chip breaking starting at pressures in the range of 40 bar, leading to a substantial improvement of process stability and productivity. But for an ... More...


 

Cooling and lubrication of machining processes with cryogenic assistance (CO2 or LN2), in combination with minimum quantity lubrication (MQL), provides high potential for increasing productivity in machining different workpiece materials (i.e. Titan, steel alloys, etc.). However, in order to exploit this potential, still missing is more comprehensive basic knowledge on cryogenic purposed cutting tools and the simultaneous delivery of both fluids (CO2 and MQL) through the small cutting tools (d < 12 mm). Just in this way, the objective of flexible and successful delivery through the machine tool spindle and small tool diameter cutting tools, supplying both fluids on the machining centers (MC) and into the drilling and milling processes, can be realized. The overall objective of the project is ... More...


 

Do you have questions concerning this research area?

Your contact:
Dipl.-Wirt.-Ing. Tolga Cayli
 
Cluster Produktionstechnik 3A 248
Tel.: +49 241 80-20524
Fax: +49 241 80-22293
Mail: T.Cayli@wzl.rwth-aachen.de

 

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