Process for the manufacture of a containment device and a containment device manufactured thereby

Abstract

A process for manufacturing a containment device including: providing steel slab including (in wt. %) C: 0.05%-0.4%; Si: ≦2.0%; Mn: ≦2.0%; P: ≦0.1%; N: ≦200 ppm; remainder iron and inevitable impurities; hot rolling the slab to steel strip after reheating the slab, or utilizing the casting heat by hot-charging the slab, or by direct rolling the slab after casting, followed by cooling the strip to coiling temperature and coiling; cold rolling the strip at between 40 and 95% thickness reduction to form cold-rolled strip; continuous annealing by reheating to temperature above Ac1, homogenising at least 5 seconds, followed by rapid cooling; producing the device. The device has steel at least 10 vol. % martensite and/or bainite and reduced properties of anisotropy. Containment device manufactured by the process and producing isolation barrier material for high temperature and/or pressure sealing for containment devices are also disclosed.

1 . Process for the manufacture of a containment device comprising the steps of
 a) providing a steel slab having a chemical composition comprising (in weight percent)
 C: 0.05%-0.4%; 
 Si: not greater than 2.0%; 
 Mn: not greater than 2.0%; 
 P: not greater than 0.1%; 
 N: not greater than 200 ppm; 
   optionally also comprising, on a weight basis
 at least one member selected from the group consisting of Cr less than 1.0%, Mo less than 1.0% and/or 
 at least one member selected from the group consisting of Nb less than 0.1%, Ti less than 0.1%, V less than 0.1%; 
 remainder iron and inevitable impurities; 
   b) hot rolling the slab to a strip after reheating the slab, or under utilisation of the casting heat by hot-charging the slab, or by direct rolling the slab after casting, followed by cooling the strip to a coiling temperature followed by coiling;   c) cold rolling the strip steel at a reduction in thickness of between 40 and 95% to form a cold-rolled strip;   d) continuous annealing by reheating to a temperature above Ac1, homogenising for at least 5 seconds, followed by rapid cooling, optionally followed by temper rolling;   e) producing the containment device,   wherein the steel in the containment device comprises at least 10% in volume of at least one phase selected from a group of phases consisting of martensite and bainite and wherein the containment device has a reduced anisotropy of properties.   
   
   
       2 . Process according to  claim 1 , wherein the steel in the containment device comprises at least 20% in volume of a martensite phase. 
   
   
       3 . Process according to  claim 1 , wherein the steel in the containment device comprises at least 80% in volume of a martensite phase. 
   
   
       4 . Process according to  claim 1 , wherein the steel is coated with metallic coating. 
   
   
       5 . Process according to  claim 4 , wherein the metallic coating is selected from a group of metallic coatings consisting of Cu, Ni, Co, Al, Zn, Ti, Cr or alloys thereof. 
   
   
       6 . Process according to  claim 4 , wherein the metallic coating is a nickel-based coating. 
   
   
       7 . Process according to  claim 1 , wherein the steel is aluminium-killed or aluminium-silicon killed. 
   
   
       8 . Process according to  claim 1 , wherein the total nitrogen content of the steel is greater than 5 ppm and/or not greater than 150 ppm. 
   
   
       9 . Process according to  claim 1 , wherein the steel is temper rolled after continuous annealing. 
   
   
       10 . Containment device manufactured according to  claim 1 . 
   
   
       11 . Containment device according to  claim 10 , wherein the containment device is a gasket. 
   
   
       12 . Containment device according to  claim 10 , wherein the containment device is a cartridge for rimfire ammunition. 
   
   
       13 . Containment device according to  claim 10 , wherein the containment device is a battery case. 
   
   
       14 . Process for the manufacture of an isolation barrier material for high temperature and/or high pressure sealing applications comprising the steps of:
 a. providing a steel slab having a chemical composition comprising (in weight percent)
 C: 0.05%-0.4%; 
 Si: not greater than 1.0%; 
 Mn: not greater than 2.0%; 
 P: not greater than 01%; 
 N: not greater than 200 ppm; 
   optionally also comprising, on a weight basis
 at least one member selected from the group consisting of Cr less than 1.0%, Mo less than 1.0% and/or 
 at least one member selected from the group consisting of Nb less than 0.1%, Ti less than 0.1%, V less than 0.1%; 
 remainder iron and inevitable impurities. 
   b. hot rolling the slab to a strip after reheating the slab, or under utilisation of the casting heat by hot-charging the slab, or by direct rolling the slab after casting, followed by cooling the strip to a coiling temperature followed by coiling;   c. cold rolling the strip steel at a reduction in thickness of between 40 and 95% into a cold-rolled strip;   d. continuous annealing by reheating to a temperature above Ac1, homogenising for at least 5 seconds, followed by rapid cooling;   e. producing the containment device   
     wherein the steel in the containment device comprises at least 10% in volume of at least one phase selected from a group of phases consisting of martensite and bainite and wherein the containment device has a reduced anisotrophy of properties. 
   
   
       15 . Process according to  claim 1 , wherein the steel in the containment device comprises at least 20% in volume of a martensite phase, the remainder comprising at least 60% in volume of ferrite. 
   
   
       16 . Process according to  claim 1 , wherein the steel in the containment device comprises at least 90% in volume of a martensite phase. 
   
   
       17 . Process according to  claim 1 , wherein the steel is coated with metallic coating by electroplating. 
   
   
       18 . Process according to  claim 4 , wherein the metallic coating is a nickel-based coating with a minimum nickel-content of at least about 85%. 
   
   
       19 . Process according to  claim 1 , wherein the total nitrogen content of the steel is between 15 and 125 ppm. 
   
   
       20 . Process according to  claim 1 , wherein the total nitrogen content of the steel is between 25 and 100 ppm. 
   
   
       21 . Process according to  claim 1 , wherein the steel is temper rolled after continuous annealing, wherein the temper rolling reduction is 10% or less. 
   
   
       22 . Process according to  claim 1 , wherein the steel is temper rolled after continuous annealing, wherein the temper rolling reduction is at least 1.5%. 
   
   
       23 . Process according to  claim 1 , wherein the steel is temper rolled after continuous annealing, wherein the temper rolling reduction is in the range from 1.5% to 10%. 
   
   
       24 . Containment device according to  claim 10 , wherein the containment device is an internal combustion engine gasket.