High Temperature Properties Stainless Steel

Stainless steel have good strength and good resistance to corrosion and oksidasi at elevated temperatures. Stainless steel are used at temperatures up to 1700° F for 304 and 316 and up to 2000 F for the high temperature stainless grade 309(S) and up to 2100° F for 310(S). Stainless steel is used extensively in penukar panas, super-heaters, ketel uap, feed water heaters, valves and main steam lines as well as aircraft and aerospace applications.

Figure 1 gives a broad concept of the hot strength advantages of stainless steel in comparison to low carbon unalloyed steel. Table 1 shows the short term kekuatan tarik dan kekuatan luluh vs temperature. Table 2 shows the generally accepted temperatures for both intermittent and continuous service.

With time and temperature, changes in metallurgical structure can be expected with any metal. In stainless steel, the changes can be softening, carbide curah hujan, or embrittlement. Softening or loss of strength occurs in the 300 series (304, 316, etc.) stainless steel at about 1000° F and at about 900° F for the hardenable 400 (410<, 420, 440) series and 800° F for the non-hardenable 400 (409, 430) series (refer to Table 1).

Carbide precipitation can occur in the 300 series in the temperature range 800 – 1600° F. It can be deterred by choosing a grade designed to prevent carbide precipitation i.e., 347 (Cb added) or 321 (Titanium added). If carbide precipitation does occur, it can be removed by heating above 1900° and cooling quickly.

Hardenable 400 series with greater than 12% chromium as well as the non-hardenable 400 series and the baja tahan karat dupleks are subject to embrittlement when exposed to temperature of 700 – 950° F over an extended period of time. This is sometimes call 885F embrittlement because this is the temperature at which the embrittlement is the most rapid. 885F embrittlement results in low ductility and increased kekerasan dan kekuatan tarik at room temperature, but retains its desirable sifat mekanik at operating temperatures.

Table 1 Short Term Kekuatan Tarik vs Suhu (in the annealed condition except for 410)

* perlakuan panas by oil quenching from 1800° F and tempering at 1200° F

Table 2 Generally Accepted Service Temperatures

It may seem to be illogical that the “continuous” service temperature would be higher than the “intermittent” service temperature for the 300 series grades. The answer is that intermittent service involves “thermal cycling”, which can cause the high temperature scale formed to crack and spall. This occurs because of the difference in the coefficient of expansion between the stainless steel and the scale. As a result of this scaling and cracking, there is a greater deterioration of the permukaan than will occur if the temperature is continuous. Therefore the suggested intermittent service temperatures are lower. This is not the case for the 400 series (both ferritic and martensitic grades). The reason for this is not known.

Referensi Terkait:
Penggunaan baja tahan karat dalam kondisi suhu tinggi lihat tabel
Tabung Baja Tahan Karat Tahan Korosi
Ketahanan Korosi dari Tabung Baja Tahan Karat
Efek Suhu pada Kekuatan Logam
Tabung Baja Tahan Karat Suhu Tinggi
Tabung Baja Tahan Karat Suhu Tinggi
Baja Tahan Karat Properti Suhu Tinggi
Tabung Baja Tahan Karat Tahan Panas
Pipa Baja Tahan Karat Dilas
Tabung Baja Tahan Karat Tekuk U
Tabung Penukar Panas
Tabung Baja Tahan Karat Duplex
Tabung Boiler, Tabung Kondensor
Tabung Pipa Baja Tahan Karat Bergelombang Bergelombang
DIN 2391 Tabung Baja Presisi Seamless
EN 10305-1 E215 E235 E355 Tabung Tabung Tabung Baja Presisi Seamless
Tabung Baja Tahan Karat yang Tidak Tahan Asam
Tabung Baja Tahan Karat Anil Cerah
Standar Tabung dan Pipa Suhu Tinggi
Sifat Teknis Baja Tahan Karat Perubahan Suhu Tinggi
Baja Tahan Karat Tahan Panas dan Baja Tahan Karat Tahan Korosi-Baja Katup, paduan Besi Baes Super
Risiko Percikan di Atmosfer Gas yang Mudah Meledak