The Research Of The Frictional Behavior Of Autosheet

The flourishing automotive industry gave birth to the increasing need of the automotive sheet. How to guarantee the excellent formability has become the key point for the competition of the automotive sheet producers.The automotive sheet's formability refers to its adaptability during the process of stamping. The formability composes of the basic formability and the simulated formability. The excellent formability is important to the decrease of the manufacturing cost of cars producers as well as the car's safety. The frictional behavior of the automotive sheet is one of the indispensable parts of the formability.The frictional behavior indicates the mutual action of the sheet and the dies during the process of stamping and it will directly influence the stamping quality. To evaluate the influence of such factors as lubricants and micro-hardness to the frictional behavior is essential to the research of the automotive sheet's stamping.Depending on the Draw Bead Simulator (DBS), the influence of lubricants, micro-hardness, drawing speed and sheet's thickness to the coefficient of friction (COF) of the automotive sheet when they were pulled through the draw bead was measured. The result showed:(1) Depending on the DBS, the research of the influence of different lubricants to the COF can be processed.(2) As to the same kind sheet, the coefficient of friction decreased with the increase of the viscosity of the lubricants.(3) As to the coating sheets with the similar mechanical properties and surface roughness, the coefficient of friction decreased with the increase of the micro-hardness of sheets when using the same lubricants.(4) Drawing speed imposed weak influence on the COF. The COF increased with too low or too high drawing speed. 0.08m/s was the best speed for the COF tested on the DBS.(5) As to the cold rolled sheets with the similar mechanical properties and surface roughness, the coefficient of friction decreased with the increase of the thickness of sheetsDepending on a numerical simulation for the data of the test, compared with the result of the theoretical data, the result has more dependability for the reality production obviously than the common theoretical data.