The UNS S31600 Stainless Steel Round Bar composition has nickel, carbon, manganese, phosphorus, sulfur, silicon, chromium, molybdenum and nitrogen in the composition. The density and the melting point of the material are similar to those of the 304 grade steel. The SS 316 Hex Bar Sizes range from 18mm to 57mm and these are stronger because of the geometrical shape.Stainless Steel Hexagonal Bars, Rod Suppliers, ManufacturersWe can supply cut to size stainless steel hexagonal bars, with both small and big widths. Our stock of stainless steel hexagonal bars includes thickness range from 6mm up to 75, with Ultrasonic Test Reports, Chemical Test Reports, as well as Mechanical Test Reports. ASTM 304/321/316 Hairline or Pickled Stainless Steel Hexagonal Bars.