Effect of humidity on grinding force of TiAl alloy at nanometer scale

TiAl alloy is a new kind of lightweight high temperature resistant structural material. Its density is only about half of that of nickel-based superalloy. It is an excellent substitute material for nickel-based superalloy. TiAl alloy is a brittle material that needs to be processed in the plastic domain on the nanoscale. Due to the influence of humidity, a thin water film will inevitably condenses on the processed surface. Therefore, it is necessary to consider the role of humidity in nanofabrication. The results show that when the water layer thickness is 0, 4 Å and 8 Å, the maximum tangential grinding force is 165 nN, 266 nN and 386 nN, and the maximum normal grinding force is 517 nN, 521 nN and 528 nN, respectively. Compared with the normal grinding force, the stress value of tangential grinding force changes more obviously. The variation of the peak value of radial distribution function (RDF) around Al atoms before and after grinding is smaller than that of Ti. From the second peak to the sixth peak, with the increasing of the water layer thickness, the peak of the wave crest gradually decreases. When the grinding wheel is rotating forward, the maximum tangential grinding force is 266 nN and the maximum normal grinding force is 521 nN, when the wheel is rotating backward, the maximum tangential grinding force is 497 nN and the maximum normal grinding force is 451 nN.