High intensity variable section spring piece under high stress and method for producing the same

Abstract

The invention relates to a high-strength variable cross-section reed which can bear high-stress, comprising the components with mass mixture ratios as follows: 0.46 to0.62 percent of C, 0.20 to 2.00 percent of Si, 0.30 to 0.90 percent of Mn, 0.8 to 1.20 percent of Cr, 0.10 to 0.20 percent of V, 0.005 to 0.1 percent of Al, and the rest of Fe and impurity. The manufacturing method of the reed is that: temperature control and variable cross-section rolling is carried out to a spring flat steel which has the components and mass mixture ratios under 700 DEG C to 950 DEG C to form the variable cross-section reed which is then heated to 86 DEG C to 950 DEG C for quenching, tempering is carried out at temperature of 380 DEG C to 450 DEG C, and then stress shot blasting is carried out to the pulled stress surface by adopting the steel shot with diameter from 0.8 mm to1.0 mm at the speed of 50 to 90mm / s under the bending stress of 800MPa to 1600MPa. The high-strength variable cross-section reed effectively solves the problem that fatigue property on the surface and the inside defect sensibility is significantly increased under the high stress condition after the strength is improved, the tensile strength is more than1800MPa, and the performance thereof is much better than the performance level of domestic spring and achieves the international leading level.

Description

Technical field: [0001] The present invention relates to a high-strength variable-section reed that bears high stress and a manufacturing method thereof, in particular to a high-strength variable-section reed that bears high stress and has a high-strength variable-section reed that has a tensile strength above 1800 MPa and has good fatigue performance under a high-stress state and its manufacture method. Background technique: [0002] The weight of the leaf spring suspension system used in light passenger cars and large and medium-sized trucks accounts for 8-9% of the vehicle's own weight. Therefore, the lightweight of the leaf spring suspension system plays an important role in reducing the weight of the vehicle. The design of the variable cross-section less-leaf spring has the advantages of less number of reeds, light weight, and good ride comfort. At present, in foreign industrialized countries, a few-leaf leaf spring composed of one or two or three longitudinal variable...

AI Technical Summary

Problems solved by technology

[0003] The object of the present invention is to provide a high-strength variable-section reed that bears high stress in order to solve the defects of existing reeds with low stress level and low strength level. The tensile strength of the reed is above 1800MPa and the Good fatigue properties under stress