a) Classification of Stainless Steel
Including the stainless steel high alloy steel that is resistant to corrosion, high temperature and low temperature. Besides, it also has the toughness and character are Able to cut enough. Because of its nature, the steel is Widely used in atomic reactors, turbines, jet engines, aircraft, household appliances and others. Broadly speaking, stainless steel can be classified into three types, namely, type of ferrite, austenik types, types of martensite.
Properties of stainless steels
Stainless steel have different properties with both carbon steel and low alloy steel with roomates greatly Affect the properties of nature capable of welding. The chemical composition and mechanical properties, as well as the physical properties and the low alloy steel roomates greatly Affect the properties of nature capable of welding. Master alloys of stainless steel or Cr Cr and Ni with a few additional elements such as Mo, Cu, and Mn. Of the physical properties indicates that the coefficients roomates expands approximately 1.5 times soft steel, then in stainless steel welding will be changes in larger form. As an example of the tensile strength stainless steels at high temperature as shown in Figure 1.1., While the strength of her mouth (1% in 10.000 hours).
b) Welding In Stainless Steel (Stainless Steel)
Welding with covered electrodes, MIG welding and TIG welding is a method that is Widely used in welding stainless steels at this time. Besides, it is sometimes used too faint arc welding, electron beam welding and electric resistance welding. Because stainless steel is high alloy steel, it is clear that the quality of the welding connection is strongly influenced by the heat and Become brittle and atmospheric welding. Weldability properties of each type stainless steels are described below:
Including the stainless steel high alloy steel that is resistant to corrosion, high temperature and low temperature. Besides, it also has the toughness and character are Able to cut enough. Because of its nature, the steel is Widely used in atomic reactors, turbines, jet engines, aircraft, household appliances and others. Broadly speaking, stainless steel can be classified into three types, namely, type of ferrite, austenik types, types of martensite.
Properties of stainless steels
Stainless steel have different properties with both carbon steel and low alloy steel with roomates greatly Affect the properties of nature capable of welding. The chemical composition and mechanical properties, as well as the physical properties and the low alloy steel roomates greatly Affect the properties of nature capable of welding. Master alloys of stainless steel or Cr Cr and Ni with a few additional elements such as Mo, Cu, and Mn. Of the physical properties indicates that the coefficients roomates expands approximately 1.5 times soft steel, then in stainless steel welding will be changes in larger form. As an example of the tensile strength stainless steels at high temperature as shown in Figure 1.1., While the strength of her mouth (1% in 10.000 hours).
b) Welding In Stainless Steel (Stainless Steel)
Welding with covered electrodes, MIG welding and TIG welding is a method that is Widely used in welding stainless steels at this time. Besides, it is sometimes used too faint arc welding, electron beam welding and electric resistance welding. Because stainless steel is high alloy steel, it is clear that the quality of the welding connection is strongly influenced by the heat and Become brittle and atmospheric welding. Weldability properties of each type stainless steels are described below:
The nature of weldability of stainless steels:
1. Martensitic stainless steel type
Steel is in the heating and cooling cycles during the welding process will form martensite so hard and eddc3getas Able unfavorable welding properties. In a stainless steel weld this type must be Considered two things:
1. Martensitic stainless steel type
Steel is in the heating and cooling cycles during the welding process will form martensite so hard and eddc3getas Able unfavorable welding properties. In a stainless steel weld this type must be Considered two things:
- Should be given first heating to a temperature between 200-400 ° C and temperature of the welding between layers must be held not to be too cold.
- Immediately after completion of welding temperature should be held between 700-00 ° C for some time.
2. Stainless steel type ferrite
Stainless steel hardened type of ferrite is very difficult, but it is easy to be coarse grain roomates causes Decreased toughness and Tenacity. Embrittlement Welding Occurs in slow cooling from 600 ° C to 400 ° C. Because of this nature then the steel welding should be done first heating from 70 to 100 ° C to avoid cold cracking and cooling from 600 ° C to 400 ° C must happen Quickly to avoid embrittlement as Explained above.
3. Austenitic stainless steel
This type of stainless steel has a nature capable lasa better when Compared with the other two types. But even then the slow cooling from 680 ° C to 480 ° C will form a chromium carbide precipitates between grains. This sediment Occurs at Temperatures around 650 ° C and led to Decreased resistance to corrosion and mechanical properties. Mechanical properties and corrosion resistance properties of the weld metal is strongly influenced by the chemical composition and structure. Since all types of stainless steels in welding will undergo embrittlement and cracking, the weld metal should always be kept in a secure area lies in gambar1.3. (Local ER 308). Austenite structure will lead to heat cracking formation as shown in Figure 1.4. But the heat is greatly reduced crack when austenite containing more than 4% ferrite. With the above properties in welding austenitic stainless steels should: first do not do warm up first, but avoid the high heat input so that no precipitation Occurs between grains of carbide-chrome, the second should be used electrode type of Nb, Ti or low carbon (C ≤ 0, 03%) and three selected electrodes produce weld metal structures in a safe area of the Schaeffler diagram.
Stainless steel hardened type of ferrite is very difficult, but it is easy to be coarse grain roomates causes Decreased toughness and Tenacity. Embrittlement Welding Occurs in slow cooling from 600 ° C to 400 ° C. Because of this nature then the steel welding should be done first heating from 70 to 100 ° C to avoid cold cracking and cooling from 600 ° C to 400 ° C must happen Quickly to avoid embrittlement as Explained above.
3. Austenitic stainless steel
This type of stainless steel has a nature capable lasa better when Compared with the other two types. But even then the slow cooling from 680 ° C to 480 ° C will form a chromium carbide precipitates between grains. This sediment Occurs at Temperatures around 650 ° C and led to Decreased resistance to corrosion and mechanical properties. Mechanical properties and corrosion resistance properties of the weld metal is strongly influenced by the chemical composition and structure. Since all types of stainless steels in welding will undergo embrittlement and cracking, the weld metal should always be kept in a secure area lies in gambar1.3. (Local ER 308). Austenite structure will lead to heat cracking formation as shown in Figure 1.4. But the heat is greatly reduced crack when austenite containing more than 4% ferrite. With the above properties in welding austenitic stainless steels should: first do not do warm up first, but avoid the high heat input so that no precipitation Occurs between grains of carbide-chrome, the second should be used electrode type of Nb, Ti or low carbon (C ≤ 0, 03%) and three selected electrodes produce weld metal structures in a safe area of the Schaeffler diagram.
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Tagged @ Welding Stainless Steel
