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Stainless steel AISI 304 L is very common in use and most versatile steel of all stainless steels. Chemical, mechanical properties of AISI 304 L, resistance to oxidation, corrosion and good weldability determine the optimal ratio price/quality. Steel AISI 304 L has not only excellent low-temperature properties, but also recommended for use in high-temperature zone and the risk of intergranular corrosion.

The characteristics of steel

In the production process of steel AISI 304 L 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).

Application

Steel grade AISI 304L is used in all domestic, commercial, industrial sectors due to its 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.

Percentage composition of 304L .

AISI	C	Cr	Fe	Ni	V	Mn	P	S	Si	Impurities
304 L	≤0,03	18−20	DOS.	8−12	---	≤2	≤0,045	≤0,03	≤1	≤0,15

Mechanical properties at room temperature of AISI 304 L.

Features 304 L	At least	Typical
The elastic limit. N/mm2 Rp 0,2, (0.2%), (turnover)	170	310
Limit durable. m Rp, N/mm2 (tension)	485	590
Fatigue resistance, N/mm2	-	240
Elongation А5до relative gap in %	40	60
Brinell hardness — HB	-	170

The strength required increases with:

· termouprochnenija in the enterprise of steel (pressure; stretching; training repeated rolling; a cold deformation)

· adding in nitrogen steel

Nitrided stainless steel is used in such objects as large shipping containers, columns, tanks, where at the maximum design strength of steel (Rp0,2) it becomes possible to reduce wall thickness, saving in cost of materials. Other areas of use of austenitic steel grades AISI304 subjected to termouprochnenuju are a variety of molding plates, intended for the production of hoops for kegs, vehicles, support elements, welded pipes, straps, chains.

At high temperatures the characteristics of the

Strength limit N/mm2 (tensile), 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	50
plastic deformation Rp1,0 to 1.0% (turnover), in N/mm2	100 000 h	5	25	50	80	120
plastic deformation Rp1,0 to 1.0% (turnover), in N/mm2	10 000 h	10	30	50	80	120

At the temperature of formation of oxides:

— continuous exposure to 925 °C;

— intermittent exposure to 850 °C.

Corrosion resistance.

— Wednesday acid.
Examples for certain acidic solutions, acids

Temperature in °C	80
To the mass concentration in %	10	20	40	60	80	100
nitric-TA	0	0	0	0	1	2
ant-TA	0	1	2	2	1	0
sulfur-TA	2	2	2	2	2	2
phosphorus-TA	0	0	0	0	1	2
Temperature in °C	20
To the mass concentration in %	10	20	40	60	80	100
nitric-TA	0	0	0	0	2	0
ant-TA	0	0	0	0	0	0
sulfur-TA	2	2	2	2	1	0
phosphorus-TA	0	0	0	0	0	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 beginning of forging temperature .1150 — 1260 °C, and the end. 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 450−600^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°1020 — 1120 °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 different use. Normal operations include forming, stretching, bending, rotating and deep hood. During forming also use the same tools as for carbon steels. In this case, you will need a much larger effort by about 50−100%. 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 the material to pass freely in the instruments in practice, however, this happens not so often. For example, always takes place forming with the tension at the hood household utensils. The material that is subjected to deep drawing process 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». As for the canteens of stainless steel Cutlery, usually 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

Steel AISI 304 L lends itself to easy welding. Heat treatment, usually after welding is not required. But, at the risk of intergranular corrosion at the temperature. 1050−1150°C to produce additional autogenie. Seam welding must be cleaned of chemical and mechanical means from scale, passivated etching paste its end.

Buy at best price

The company «AVEK global» sells a range of products from steel AISI 304 L. the Popularity of this type of products due high quality products, great variety and real value. Every our products undergoes strict control throughout the production chain, 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 a required item in the basic version. The company «AVEK global» is always ready to produce quality products according to individual order.