SE526117C2 - Process for the manufacture of an ultra high-strength pressure-turned product of steel - Google Patents

Abstract

The invention relates a method for manufacturing an ultra-high-tensile sheet metal product of steel, at which the initial work piece used is constituted of a metal work piece of iron, alloyed with chromium, nickel and carbon in predetermined proportions. The initial work piece is plastically cold worked by pressure turning at a predetermined temperature and/or deformation degree that determines and is determining for the yield point of the final product, in providing a strong deformation hardening, that gives the final product a completely or partially many times increased strength, or higher yield point, as compared to the yield point of the initial work piece.

Description

temperature and at the same time to a degree of deformation adapted to the yield strength of the like product desired. If you have a low or moderate degree of deformation and want a high strength, you can compensate for this with a lower temperature, ie. by cooling before, during or after or by a combination of these criteria during the processing operation. If you have a high degree of deformation, you can counteract a deformation hardening by allowing the workpiece to maintain a higher temperature. The temperature T maintained wholly or partially during processing is -196 ° C <= T <= 70 ° C.

The invention is described in more detail below with the aid of the following exemplary embodiments.

In the preferred embodiment according to the invention, the pressure-turned sheet product manufactured according to the invention consists of a metal blank of iron alloyed with chromium, nickel and carbon in predetermined proportions. In the selected example, the iron has been alloyed with 17% Cr, 7% Ni and 0.1% C or to these adjacent alloys and the temperature T of the substance before and / or during the manufacturing process has been obtained or maintained at a controlled level, for producing during the pressure turning a strong but controlled deformation hardening during a plastic cold working of the blank in combination with the alloy maintaining good ductility.

Furthermore, the temperature T can be controlled in the preformed, pressure-turned product directly after the processing process itself.

The alloyed metal blank forming the constituent material according to the invention can be molded or plastically cold worked in traditional machine types for pressure turning to raise its yield strength from an original, low yield strength of about 300 MPa to a final product having a yield strength of more than 700 Mpa or from an elevated level of approx. 700 MPa to a higher level of approx. 1500 MPa.

Claims (6)

Patent claims 1. A process for the manufacture of an ultra-high-strength steel product, in which the constituent metal substance used is iron, alloyed with 17% chromium, 7% nickel and 0.1% carbon or related alloys, characterized in that the constituent metal substance plastically cold-worked by pressure-turning at a predetermined temperature and / or to a degree of deformation which determines and is decisive for the yield strength of the final product to obtain a strong deformation hardening which gives the final product a fully or partially multiplied increased strength or higher yield strength, the yield strength of the constituent substance, which original, low yield strength amounts to approx. 300 MPa and which higher yield strength amounts to over 700 MPa, while the temperature T at which the constituent metal blank is completely or partially cooled or the temperature T which is maintained in whole or in part during processing is -196 ° C <= T <= 70 ° C to obtain a controlled, high strength regardless of degree of deformation. Method according to claim 1, characterized in that the alloyed metal blank is formed in traditional machine types for pressure turning in order to raise its yield strength from an initial low yield strength to an end product which in whole or in part has a high yield strength. Process according to Claim 1 or 2, characterized in that the constituent is cooled completely or partially to or maintained at a controlled temperature range before and during processing in order to obtain a controlled, high strength, regardless of the degree of deformation. Process according to one of the preceding claims, characterized in that the finished product is cooled completely or partially or is kept at a controlled temperature in order to obtain a controlled increase in strength, regardless of the degree of deformation during processing. A method according to claim 4; characterized in that the temperature at which the finished product is completely or partially cooled or the temperature maintained after processing is -1A96 ° c <= T <= 70 ° C. Method according to one of the preceding claims, characterized in that the pressure roller or rollers used in the pressure turning operation are force- or position-controlled.