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The question is: do the different metallurgical processing forms of type 316 stainless steel or any other materials have an influence on the resultant mechanical properties of the same material with different processing forms? 

 

Type 316 molybdenum-alloyed austenitic chromium-nickel steel-type 316 stainless steel. 

 

Chemical composition: (percentage by mass): Carbon 0.05, Silicon 0.4, Manganese 1.7, Phosphorus 0.03, Sulphur 0.015, Chromium 17.0, Nickel 12.0, Molybdenum 2.6, Iron 66.21.

 

Type 316 stainless steel can be produced in a foundry by melting and blending all of the above mentioned constituents in the right proportions, and pouring the molten 316 stainless steel into a mould shrouded with the inert gas argon as in gravity casting, or cast into a vacuum to prevent the formation of gas bubbles or voids in the resultant casting. It is assumed that the mechanical properties of type 316 stainless steel, like tensile strength and cumulative creep rupture strength, is a simultaneous function of temperature of the material and the factor of the pseudo critical parameters conferred by the different manufacturing conditions of the metallurgical processing forms of the materials-gravity casting, vacuum casting, impact/compression by drop forging, extrusions through tungsten carbide dies with a substantial amount of constriction of cross section area of material from initial area of cross section to the resultant reduced cross section area after extrusion of material.

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George Xanthopoulos
Enfield, South Australia
+61(4)52651966
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The short answer is YES. 
Wrought materials typically are stronger than castings.
The fine substructure of welds often makes then stronger than castings or annealed base metal.
Degree of cold work and time and temperature of heat treatment have a strong effect.
Even for wrought and annealed materials of equivalent strength, grain size has a strong influence on creep and stress rupture resistance.

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John Grubb
consultant
New Kensington PA
(724) 448-5272
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To elaborate a little more on John's summary:  Calling out an alloy steel as "316" merely gives a general classification of the weight percent of alloying elements.  Strictly speaking there is not a "cast 316" grade, as the requirements in the various industry specifications for alloy castings have different designations, and percentages of alloy, which are suitable for the casting production process.  An example might be CF-8M. 

But you can produce alloy materials by ingot metallurgy, direct / continuous casting, various processes referred to as traditional casting, powder metallurgy, additive manufacturing by welding or laser or other form of net shape processing.  And then you can process any of those alloy forms by heat treatment, hot rolling, cold rolling, forging, piercing, extrusion, and/or surface treatments, and EACH of these combinations of original production and subsequent processing steps will result in a different combination of mechanical & physical properties, and/or corrosion resistance.  So it is important to know what the desired combination is, and to choose an appropriate industry specification that will be targeted towards your needs.

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Paul Tibbals
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