Relevance

Steel AISI 304 is one of the most versatile and has a wider distribution and use in comparison with other stainless steels. Chemical, mechanical characteristics, resistance to oxidation, corrosion and good weldability — is the best ratio price/quality. Steel AISI 304 has excellent low temperature properties and is recommended for use in high temperature zone in cases of intergranular corrosion.

Application

Steel grade AISI 304 is used in all commercial, industrial sectors due to high temperature and corrosion resistance. For example:

-·industrial equipment for chemical, cryogenic, food, mineral, dairy, pharmaceutical industries;

— in the manufacture of reservoirs and containers for different liquid, dry substances.

Dignity

In the steel production process are set the following special properties that characterize the use and its subsequent processing:

-improved weldability;

rotary cooker hood, deep drawing;

-forming stretching;

-machining;

-cold deformation. Increased strength;

-the heat resistance of Ti and C (titanium and carbon)

Percentage composition of the steel grade AISI304.

Mark	Ni	N	Mo	V	Ti	Cr	C	Si	Mn	P	S	Cu
AISI 304	8,0 — 10,5					18,0 — 20,0	0.08 max	1,0	2,0	0,045	0,030

Mechanical properties of AISI304 at room temperature.

Features	At least	Typical
Fatigue resistance, N/mm2	-	240
Elongation to break A5 in %	40	60
Brinell hardness — HB	-	170
Limit durable. m Rp, N/mm2 (tension)	515	600
Elasticity N/mm2 Rp 0,2, (0.2%) (creep)	205	310

The strength of steel, if necessary, increased by using:

· termouprochnenija steel enterprise (stretching; training repeated rolling; pressure; cold deformation)

· adding in nitrogen steel

Nitrided stainless steel is used in particular in objects as large shipping containers, columns, tanks, where at the maximum design strength of steel (Rp0,2) it becomes possible to reduce the thickness of its walls, as well as to save on materials costs. Other areas of use of austenitic steel grades 304, subjected to termouprochnenuju are a variety of molding plates, intended for the production of hoops for kegs, vehicles, support elements, welded pipes, straps, chains.

The characteristics of steel at high temperatures

At high temperatures tensile strength

Strength limit N/mm2 (tension), Rp m		380	270	170	90	50
Temperature in °C		600	700	800	900	1000

The minimum value at high temperatures the elastic limit (within a set time warp B1% at given temperatures)

Temperature in °C	Time	800	700	650	600	550
plastic deformation Rp1,0 to 1.0% (turnover), in N/mm2	10 000 h	10	40	70	100	180
plastic deformation Rp1,0 to 1.0% (turnover), in N/mm2	100 000 h	5	25	50	80	120

Scale formation at temperatures

Recommended maximum temperature service.

continuous exposure to 925°C

intermittent exposure to 850°C

Performance at low temperatures steel AISI 304:

Temperature	°C	-161	-78	-196
Limit durable. m Rp, N/mm2 (tension)	N/mm2	1450/1200	1100/950	1600/1350
Limit durable. m Rp, N/mm2 (tension)	N/mm2	380/220	300/180	400/220
The viscosity of the shock	J	160/160	180/175	155/150

The resistance to corrosion.

-in acidic environments.
examples for certain acidic solutions, acids

Temperature in °C	20
To mass concentration, %	10	20	40	60	80	100
Nitric	0	0	0	0	2	0
ant to	0	0	0	0	0	0
sulfur to	2	2	2	2	1	0
phosphoric to	0	0	0	0	0	2

Temperature in °C	80
To mass concentration, %	10	20	40	60	80	100
nitric	0	0	0	0	1	2
ant to	0	1	2	2	1	0
sulfur to	2	2	2	2	2	2
phosphoric to	0	0	0	0	1	2

Code:
-Partial protection is equal to 1. The corrosion rate 100m to 1000 mm/year.

— High degree of protection equal to 0. The corrosion rate of 100 mm/year.

— Non resistant equal to 2. The corrosion rate свыше1000 mm/year.

Treatment of thermal

The range of forging. The beginning of the process t°. — 1150 — 1200 °C, the end of the process. t°.900−925°C. the Period of time estimated to obtain a homogeneous heating of stainless steels longer than carbon-12. Relief (or release) method of autogene without showing deposition of carbide is in a temperature range of 450−800^o C. thus, the departure from microlimano possible corrosion. Gradual lowering of the temperature necessary to safeguard the allocation of carbon. The annealing is carried out at t°1050 — 1150 °C cooling and the sharp intake of cool air, providing maximum ductility of the steel.

Treatment cold

Due to its strength, this steel finds a variety of use. Typical operations include bending, forming by stretching, rotating and deep hood. At the time of molding using the same tools as for carbon steels. In this case, it will take much more effort is approximately 1.5−2 times. This makes babout thegreater degree of hardening when forming austenitic steel, but in certain cases may also serve as a negative factor.

Hood Rotogravure

During deep drawing of the workpiece to the press was not subjected to «braking», and give freely to pass in the instruments in practice, however, this happens not so often. For example, always takes place forming with stretching in the manufacture of the cookware. The material, which is subjected to deep drawing must have when forming a low degree of hardening, i.e. to be stable at the maximum, and the rate of Md30 (N) have to be «in the red». For kitchens stainless steel appliances are typically used so-called sub-tests of stainless steel stock as in the production of pots by deep drawing. In flow-forming machine rotary extractor means forming with the turning.

Forming, stretching

In the period of forming, stretching is subjected to a preset «inhibition». Its walls become very thin during forming, to avoid a gap, preferably of steel to provide the characteristics of high strengthening.

Welding

Of AISI304 weldable easily.

Welding. Process	Without taking into account the weld thickness	Given St seam thickness			Environment protective
						Thick.
							Rod	Wire
						Resistance -spot. Seam (seam) -(point)	≤2mm
PLASMA	<1.5 mm	>0.5 mm	ER 310	ER 308 l (Si) W. Nr 1.4370 ER 347 (Si)	Argon Argon + 5% Hydrogen Argon + Helium
TIG	<1.5 mm	>0.5 mm	ER 308 l (Si) W. Nr 1.4370 ER 347 (Si)	ER 308 l (Si) W. Nr 1.4370 ER 347 (Si)	Argon Argon + 5% Hydrogen Argon + Helium
.MIG		>0.8 mm		ER 308 l (Si) W. Nr 1.4370 ER 347 (Si)	Argon+ 2% CO2 Argon+ 2% O2 Argon+ 3% CO2 + 1% H2 Argon+Helium
Electrode		Repairs	E 308 E 308L E 347
S. A. W.		>2mm		ER 308 L ER 347
Laser	<5mm				Helium. Sometimes Argon, Nitrogen.

Post-weld heat treatment usually not necessary. But, in the presence of a risk of intergranular corrosion is carried out at temperatures 1055−1155°C additional autogenie. Seam welding must be cleaned of chemical and mechanical means from scale and passivated using a pickling paste.

Buy at best price

All the demands of consumers completely satisfied with the products, which are produced from AISI 304 the company «AVEK global». The popularity of this type of products due high quality products, great variety and real value. Any our products are held absolute control throughout the manufacturing process, to guarantee absolute high quality of our steel products. Modern technological capabilities at any stage of production provide the opportunity to carry out individual orders in the absence of the required items in the basic version. The company «AVEK global» is always ready to produce high-quality steel non-standard options to order.