The Study Of Increasing The Mechanical Property Of The Heavy Rail

In order to comprehensively under stand the conditions of chemical composition and mechanical properties of the steel rails produced in Angang, the ones produced from July, 2005 to Feb.,2006 are statisticed and analyzed. At last property regression equation related to chemical composition was expressed. Moreover through the experiment we can find out the every kind of factor affect the impact tenacity of heavy rails, and brought up the measure to solve the problem, and increased the qualified rate of the impact toughness of the heavy rails. Conclusions were gained as follows:(1) The chemical composition range of heavy rail that produced by Angang large mill was narrow, the content of P and S is little, U75V as the high strength heavy rail, its tensile strength is higher about 90MPa than U71Mn heavy rail, its elongation percentage is lower about 1%. In recent year, the improving of the process and the increasing of product level of Angang heavy rail made the inherent quality of heavy rail increased obviously and the performance steady.(2) The little change of element of C,Si,Mn,P,S will influence the property of the heavy rail, we can improve the tensile strength and elongation percentage of the heavy rail by the way of optimizing the chemical composition.(3) The regression equation we got described the process present state of Angang heavy rail is adapted to the effective regression equation used by Angang. Using this regression equation can presume the property by the specific chemical composition, it supply the possibility of simplying the check.(4) The finishing temperature and beginning temperature is the chief factor of influencing the heavy rail's impact toughness. Reducing the finishing temperature can increasing the impact toughness.(5) The heating time and heating temperature in the heating furnace influenced the impact toughness of the heavy rail widely, reducing the soaking time and heating temperature can increase the impact toughness.(6) Slowing cool process and the way of charging also effect the impact toughness, using the Slowing cool process and cold charging can increase the whole mechanical property. All of the above conclusions are useful to guiding the product of heavy rail.