Production method of binding strap with tensile strength more than or equal to 1000MPa

Abstract

The invention discloses a production method of a binding strap with tensile strength more than or equal to 1000MPa. The method comprises the following steps: cold-rolling a pickled 30Mn2 hot-rolled coil; uncoiling, stripping and removing burrs, and then carrying out high temperature austenitizing; quenching the coil in a mixed solution consisting of triton X-100, Tween 20 and water; washing with water as conventional means and tempering the coil; naturally air-cooling to room temperature; and coiling. A finished product of the invention is 0.8-1.0mm thick, 1030-1070MPa in tensile strength, 10-12% in elongation rate and no less than 4 times in repeated bending time, and a blue layer which is uniform and dense, strong in adhesive force and 4-6microns thick is generated on the surface. The performances of the finished product completely meet the demands of binding and packaging heavy-coil hot-rolled steel coils.

Description

technical field [0001] The invention relates to a production method of a strap, in particular to a production method of a strap with a tensile strength ≥ 1000 MPa. Background technique [0002] Ultra-high-strength strapping is a high-value-added cold-rolled deep-processing product, which is widely used in bundling and packaging of large and heavy hot-rolled steel coils. Generally, it should have "tensile strength not less than 980 MPa, elongation not less than 10%, the number of repeated bending is not less than 4 times (R=2.5 mm), and the surface forms a layer with a certain thickness, strong adhesion, uniform and dense bluish layer "and so on. [0003] Generally speaking, due to the large scale of heavy hot-rolled steel coils on the surface, they only need to be bundled with blued straps to reduce packaging costs. At the same time, due to its heavy weight, the straps need to have high strength, plasticity and toughness to prevent the straps from breaking during bundling. ...

AI Technical Summary

Problems solved by technology

However, this process also has an obvious disadvantage: a small amount of oil is likely to remain on the surface of the steel strip after quenching, which is difficult to clean and will affect the surface quality of the product; at the same time, the residual oil is also prone to burning during tempering, causing a fire ACCIDENT

However, this process also has a disadvantage: the cooling ability of the molten nitrate is weak, it takes a long time to cool to the required temperature and the corresponding structural transformation occurs, and it is easy to make the steel with low stability of supercooled austenite pearlite formed during cooling

In addition, due to the long cooling time, production often needs to be carried out at a slow speed, which will lead to low work efficiency and increased production costs

Images