Process Research And Optimization Of Φ0.018mm Ultra-fine Stainless Steel Wire Drawing

Stainless steel ultra-fine wire production is a new type technique that integrates with metallurgy, model manufacture, chemical process etc. techniques, which is the deep extension of common steel wire drawing technique. This article sets the uni-drawing ultra-fine stainless steel wire production technique as the research aim. Starting to analyze from the wire drawing performance of different production technique processes, and combining metallographic analysis, wire drawing mechanics performance test, SEM micro-structure observation, XRD analysis etc. different experiment research methods. Specifically researches the differences of product's characteristics and the influence to the wire drawing performance.During the period of wire drawing, it occurs the crystal lattice distortion due to the big uneven deformation, and the crystal grain broken phenomenon is very serious. With the wire drawing process, the crystal grain along the pulling direction is pulled into fiber and appeared like a silk structure; its macro appearance is with the reduced of fine wire's diameter, the tensile strength is bigger and bigger, whereas the elongation is greatly decreased. With the super large of deformation, the ultra-fine austenitic stainless steel fine wire appears more and more strong magnetism. The magnetism disappears after annealing. Corresponding to the different hot processing, there is large difference between the before and after of annealing fine wire mechanics performance and metallographic structure.Through theoretical analysis and great amount of direct actual productions, it is found that the wire broken rate is obviously different while pulling the same specification's fine wire in the case of annealing and non-annealing. The easiest occurrence of wire broken is at the beginning of wire drawing; the wire broken rate is higher and higher with the increase of wire drawing speed at the same process condition and same specification. The model consumption of high speed pulling is lower than the low speed one; the specification of model-match is the most key factor of affecting the smooth of wire drawing, the size of model input angle has great influence on the wire drawing broken rate. This thesis is finally made a set of actual production criterion that is suitable for the actual production condition of enterprise. The parameter setting, lubrication condition, annealing parameter, model selection, model-match specification of wire drawing machine after optimization may provide theoretical and practical guideline for the future ultra-fine wire production.