Copper Steel for Cartridge Case

Product Description

Copper-steel composite material with good elongation, high bonding strength, low resistivity, high tensile strength and low cost is provided. A copper-steel-copper composite material is disclosed. Its chemical composition proportion is 5-20% of copper and 80-95% of steel, and its structure is composed of copper and steel. The invention also discloses the preparation method of copper-steel composite material. The preparation steps are as follows: after surface treatment, copper and steel are rolled into high-precision steel strip and high-precision copper strip by cold rolling mill; after surface cleaning, surface residues are removed and degreased; high-precision copper-steel composite strip is rolled by cold rolling mill; and copper-steel composite strip is annealed at 650-850 C in vacuum furnace. In 1-4 hours, the structural molecules of the composite layer of two kinds of metal materials are melted, and then cooled to room temperature in vacuum furnace; the two kinds of strips are compounded to make the strips compounded into one and finish rolling; the composite materials are smoothed and polished, and the strips are packed after shearing according to the requirements of users.

Military industry: Copper-steel composite material temperature and pressure-penetration composite technology is a new technology emerging in the field of domestic metal composite strip materials, in addition to the high strength, good heat resistance, thermal stability, plasticity and corrosion resistance common to composite materials In addition to the characteristics of resistance and abrasion resistance, in the field of military bullet manufacturing, there are also the advantages of high yield and high dimensional accuracy, which are beneficial to improve the quality of bullets; the composite material has good consistency, thereby ensuring the consistency of the bullet and the shell; One batch is heavy and can be processed continuously, which greatly improves the production efficiency of bullets. The surface quality is excellent, comparable to pure copper; the brass on the surface of the copper-steel composite material also has a lubricating effect, which can reduce the impact on the barrel when shooting The wear and tear of the barrel and rim. It has been widely used in military products such as bullet shells and detonators. The sales network of military copper-steel composite materials has covered the world and won unanimous praise from many customers.
i)Military Products

Standard size	Brass-steel-brass	Brass-steel-brass	Brass-steel-brass
Strip width	139.5mm	124/135/137/140mm	< 600 mm
Strip thickness	1.7-3.6mm	0.5-1.37mm	0.05-4.0 mm
Coating thickness	3.4%-4%	3.4%-4%	3%-15 %
Base material	F18 steel	F11 steel	SPHC steel
Cladding material	H90 copper	H90 copper	H90 copper
Delivery form	Coil / Strip	Coil / Strip	Coil / Strip

 

ii)Chemical Composition

Grade	Chemical composition of steel strip
	C	Si	Mn	P	S	Ni	Cr	Cu	Als
	%	%	%	%	%	%	%	%	%
F11	≤0.11	≤0.06	0.30-0.55	≤0.02	≤0.01	≤0.3	≤0.15	≤0.2	0.02-0.1
F18	0.11-0.19	≤0.06	0.35-0.55	≤0.02	≤0.01	≤0.3	≤0.15	≤0.2	0.02-0.1
SPHC	≤0.15	≤0.05	≤0.6	≤0.035	≤0.035	-	-	-	≥0.010

 

Grade	Chemical composition of copper strip
	Cu+Ag (min)	P	Bi	Sb	As	Fe	Pb	S	Zn	Total impurities
	%	%	%	%	%	%	%	%	%	%
H90	88-91	-	-	-	-	≤0.1	≤0.02	-	allowance	≤0.2

iii)Mechanical properties and metallographic structure

 

material	tensile strength(Mpa)		Elongation(%)		Grain size	Pearlite	Non-metallic inclusionsA/B/C/D
	Annealed	half hard	Annealed	half hard
H90/SPHC/H90	290~355	360~455	≥36%	≥8%	7-10	1-5	≤2.5
H90/F11/H90	265~365	-	≥43%	-	7-10	1-5	≤2.5
H90/F18/H90	305~395	-	≥37%	-	7-10	2-6	≤2.5

Equipment and workshop