| The main research of the topic is the high-speed steel cutter which treated by phosphate admixture nano-meter K2Ti4O9 Whisker-enhanced solid-lubricating coatings, and then the processed high-speed steel cutter was assembled to ultra-precision lathe for research of turning cutting.The experiment using the SB-CNC ultra-precision CNC lathe for machining, 9257B type data record and analysis instrument turning three to force measurement, HiSpec high-speed camera records chip deformation process, JSM-7001F scanning electron microscope microstructure analysis, HCC-24 PC coating thickness measuring instrument for phosphating film thickness testing, UMT-2 type friction test machine tribological performance testing, WS-2000-type scratch test machine film and the substrate binding test.At present, the use of carbide blades are very popular, it is presumed to paint the solid lubricant coating on the carbide blade to carry out dry cutting without coolant, in this case, drawbacks caused by the use of coolant can be avoid, and the blade life can be greatly extended, meanwhile considerable economic and social benefits can be achieved. But during the process of actual application, it is difficult to mix the coating and carbide blade together, the surface is easy to produce crackling and falling, therefore phosphate admixture nano-meter K2Ti4O9 Whisker-enhanced solid-lubricating coatings were adopted on the high-speed steel cutter in this topic, the coated and uncoated high-speed steel cutting tools were assembled to the ultra-precision lathe for turning separately, by changing three cutting elements, which are cutting speed, depth of cut, feed rate, the turning were carried out under two kinds of cutting state which were the dry cutting and kerosene cooling. The size of the cutting force along X, Y, Z directions were measured by three-Dynamometer accurately, and the amount of tool flank wear were measured, the roughness of the treated work-pieces were measured, composition analysis were carried out by EDX, the forming process of iron filings were recorded by high-speed camera, and then the cutting mechanism was explored, and the excellent lubricating effect were obtained by using phosphate admixture nano-meter K2Ti4O9 Whisker-enhanced solid-lubricating coatings. It is hoped to obtain some empirical data before making a thorough study.The pilot study reached the following conclusions:(1) It can be found from the testing results that the best phosphating process is Zn(NO3)2 20g/L, Mn(H2PO4)2 60g/L, Mn (NO3)2 15 g/L, Ni (NO3)2 2 g/L, Ca(NO3)2 2 g/L, tartaric acid 1g/L, some addition. 60-70℃, 10-15min. Composite phosphate coating is a black film with fine acicular crystal. Surface-adjust before phosphating can improve the quality of phosphate coating.(2) The K2Ti4O9 whisker is added to the solid lubrication filmcomposed of Graphite+MoS2. The experimental result shows that with the K2Ti4O9 whisker' s add, the adhesion between solid lubrication and basal body is enhanced, the coefficient of friction of solid lubrication film is decreased, and the wearing life of the solid lubrication film is prolonged. Adhesion between bonded solid lubrication film and basal body is about 5.32N.(3) Phosphating before bonded solid lubricant has great effect.With phosphating before spraying solid lubricant , the coefficient of friction of solid lubrication film is smoother , the wearing life of solid lubrication film is longer. Because composite phosphate coating is a black film with fine acicular crystal. It can absorb solid lubricant, increase the contact area between solid lubrication film and basal body, so as to enhance the adhesion between them. The adhesion can be improved from 5. 32N to 11.28N.(4) After the wear-resistant composite phosphate coating of solidlubricant in the high-speed steel cutting tools, through the actual cutting of comparison, to achieve dramatic results, reducing friction and wear, improve service life.(5) High-speed steel cutting tools solid lubricating coatings canimprove the cutting process of self-lubrication conditions, can greatly enhance the cutting tool, the effect is better than cutting fluid. Application of coated tools can reduce the cutting force and improve workpiece surface quality.
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