Method for generating metallic components having customised component properties

Patent metadata

Field	Value
Publication number	US-2021017617-A1
Application number	US-201816955961-A
Country	US
Kind code	A1
Filing date	Dec 21, 2018
Priority date	Dec 22, 2017
Publication date	Jan 21, 2021
Grant date	—

Abstract

The invention relates to a method for producing a sheet steel component by means of a press hardening or form hardening process, the sheet steel component being produced by virtue of the fact that a sheet bar composed of a dual-phase steel is cold-formed, then heated, and then quenched in a cooling press or a sheet bar composed of a dual-phase steel is heated to a temperature above the austenitization temperature of the highly hardenable steel material and is then formed into the sheet steel component in a single stroke or in a plurality of strokes in a forming and cooling press, wherein a dual-phase steel is used, whose Ac3 value is increased until at the required annealing temperatures, only a partial austenitization of the dual-phase steel takes place so that when loaded into the cooling press, the dual-phase steel has a ferritic matrix, and in addition to this, austenite is present.

First claim

1 . A method for producing a sheet steel component by means of a press hardening or form hardening process, comprising the steps of:
providing a steel sheet bar including a dual-phase steel; and either a) cold-forming the steel sheet bar, then heating the steel sheet bar to an annealing temperature, then quenching the steel sheet bar in a cooling press, or b) heating the steel sheet bar to an annealing temperature, above an austenization temperature of the highly hardenable steel and forming and quenching the sheet bar using one or more strokes in a forming and cooling press; wherein the dual phase steel has an Ac1 temperature and an Ac3 temperature, and the Ac3 temperature increases during the heating so that only partial austenization of the dual phase steel occurs, yielding a matrix that includes ferritic and austenitic components when the dual phase steel enters the cooling press.

2 . The method according to claim 1 , wherein the annealing temperature is greater than about 800° C. and less than the Ac3 temperature of the dual phase steel.

3 . The method according to claim 1 , wherein the heating step is performed in a furnace using a dwell time of between about zero and about 600 seconds.

4 . The method according to claim 3 , wherein one the Ac3 value of the dual-phase steel is high enough that the degree of austenitization occurring with the dwell time and the temperature is between 50 volume % and 90 volume %.

5 . The method according to claim 1 , wherein the quenching in a) orb) is performed at a cooling rate.

6 . The method according to claim 1 , wherein the steel sheet bar is formed using a press having a loading temperature between 450 and 850° C.

7 . The method according to claim 6 , wherein the loading temperature is 700° C. to 850° C.

8 . The method according to claim 6 , wherein the loading temperature is 400° C. to 650° C.

9 . The method according to claim 5 , wherein the cooling rate is ≥10 Kelvin/sec.

10 . The method according to claim 1 , wherein the dual-phase steel contains 0.5 to 1.5%.

11 . The method according to claim 1 , wherein the annealing temperature is set so that the dual-phase steel is intercritically annealed at a temperature between its Ac1 and Ac3 temperature.

12 . A dual-phase steel material, comprising the following composition in mass %:

C
0.02-0.12%, 

Si
0.5-2.0%,

Mn
0.5-2.0%,

Cr
0.3-1.0%,

Al
0.5-1.5%,

Nb
 <0.10%,

Ti
 <0.10%

Residual quantities of iron and smelting-related impurities.

13 . The material according to claim 12 , wherein C=0.04-0.10 mass %.

14 . The material according to claim 12 , wherein Si=0.5-1.50 mass %.

15 . The material according to claim 12 wherein Mn=0.60-1.50 mass %.

16 . The material according to claim 12 , wherein Cr=0.45-0.80 mass %.

17 . The material according to claim 12 , wherein Al=0.50-1.20 mass %.

18 . A steel having a dual-phase structure, comprising:
a ferritic matrix; and martensite inclusions embedded within the ferritic matrix; wherein the steel comprises the following elements:

C
0.02-0.12%, 

Si
0.5-2.0%,

Mn
0.5-2.0%,

Cr
0.3-1.0%,

Al
0.5-1.5%,

Nb
 <0.10%,

Ti
 <0.10%

Residual quantities of iron and impurities.

19 . The steel of claim 18 , comprising:

C
0.04-0.12%,

Si
0.55-1.50%,

Mn
 0.6-1.50%,

Cr
 0.45-0.8%,

Al
 0.6-1.20%,

Nb
0.01-0.10%,

Ti
0.01-0.10% 

20 . The steel of claim 18 , having the following properties:
R p0.2 of about 250 to about 500 MPa, R m of about 400 to about 900 MPa, and A of greater than 10%.

Assignees

• Voestalpine Stahl Gmbh

Inventors

• Pichler Andreas
• Kurz Thomas
• Rehrl Johannes

Classifications

• C21D8/06

  during manufacturing of rods or wires · CPC title

• C21D2211/001

  Austenite · CPC title

• C21D2211/005

  Ferrite · CPC title

• C21D1/673 Primary

  for die quenching · CPC title

• C22C38/04 Primary

  containing manganese · CPC title