MANUFACTURING METHOD OF STOCK TUBE RIGID IN DEFLECTION AND WEAK IN TORSION AS CROSS BEAM FOR PIVOT BEAM REAR AXLE OF PASSENGER CAR

摘要

PROBLEM TO BE SOLVED: To guarantee an economic and high production capacity, and to form individual method parameters in a sufficiently variable manner in the aspects of the requirements applicable as necessary. ;SOLUTION: A center long section c of a tube formed of a heat treated steel is cold-worked into a U-shape so as to be formed weak against the torsion while ensuring a torsionally rigid end section, a thus-formed tubular stock 1 is annealed at the temperature level between 850°C and 960°C at least in a local section b, and then, hardened in water at the temperature over the Ac3 transformation temperature, and then, tempered at the temperature of 200-550°C for a time longer than five minutes. Then, at least its outer surface is hardened, and a contour is realized to finally complete a pivot beam rear axle.;COPYRIGHT: (C)2001,JPO