Stainless Steel Plate 347 347H ASTM A240

347 and 347H Stainless Steel Plate Overview

347 and 347H stainless steel plate is a general purpose austenitic stainless steel with a face centered cubic structure. It is non-magnetic in the annealed condition and can only be hardened by cold working. Niobium has been added to suppress grain boundary chromium carbide precipitation. 347H is the higher carbon version of 347 plate. Due to the additional carbon present in 347H plate, it is tougher and generally more durable than 347 plate.

These grades of stainless steel plate is available in a wide range of sizes at Penn Stainless Products. They are available for purchase in thicknesses ranging from 0.188” to 4”. Plate mill plate is available in a variety of lengths and widths. For more questions or sizes of these stainless steel plates, inquire with a member of the Penn Stainless team.

Chemical Composition of 347 and 347H Stainless Steel Plate

These grades of stainless steel plate have some unique chemical properties. 347 contains no more 0.08% carbon while 347H stainless steel contains between 0.04% and 0.10% carbon. Both contain between 17.0% and 20.0% chromium, and no more than 2.0% manganese. They are made of between 9.0% and 13.0% nickel. 347 stainless steel plate contains at most 0.04% phosphorous while 347H stainless steel can only contain up to 0.03% phosphorous. It is also comprised of no more than 0.30% sulfur, at most 0.75% silicon and at most 1.0% niobium. Niobium is what gives these grades some of their unique characteristics.

Mechanical Characteristics

347 and 347H stainless steel plate have some interesting mechanical properties. To begin, both have a tensile strength of 75 ksi and a yield strength at 0.2% of 30 ksi. This grade of stainless steel has an elongation of 40%. On the Brinell hardness scale 347 and 347H stainless steel plate has hardness of 201 and on the Rockwell B scale, both 347 and 347H have a hardness of 95.

Physical Properties

This material has a density of 0.288 Ibm/in^3 at 68℉. The coefficient of thermal expansion between 68℉ and 212℉ is 9.2 min/in. Between 68℉ and 1,832℉ the coefficient of thermal expansion of 347 and 347H stainless steel plate is 11.4 min/in. The thermal conductivity of these grades of stainless steel plate is 14.7 BTU/hr-ft between the temperatures of 68℉ and 932℉. The specific heat of these grades of stainless steel plate is 0.12 BTU/Ibm between 32℉ and 212℉.

Specifications

Applications and Usage

This stainless grade is frequently used for the fabrication of equipment that must be used under severe corrosive conditions as is common in the chemical and petroleum refining industry. These stainless steel plates also have applications in the manufacturing of boiler tubes and casing, radiant super heaters, high pressure steam pipers, heat exchangers and tube. Another common application for this type of stainless steel is in the production of cabin heaters, heavy wall-welded equipment and in the aerospace industry. Aircraft exhaust stacks and collector rings are also another area in which these grades of stainless steel plate are extremely useful. These grades are also very valuable in the food processing industry, whether that be in equipment or storage vessels. For similar reasons, they also used in the pharmaceutical industry.

Processing and Fabrication Options

• Plasma cutting
• Plate saw cutting
• Shearing
• Laser cutting
• Waterjet cutting
• Forming
• Welding
• Machining
• Plate leveling

347 and 347H Stainless Steel Plate FAQs