Generally people ask the question, what is industry between 18-8, 304 and 316 stainless steel bolts and nut, for the answer to this question, you must first need to know some basic information about stainless steel bolts and nuts. 'Stainless Steel' is the general name for an oversized family or group of alloy steels that contain at least 10.5% chromium as part of their composition. At and above this level of chromium, a complex chrome-oxide surface layer forms that prevents further oxygen atoms from penetrating into the steel and thus protects the iron in the matrix from rusting and corrosion in a bolt or a nut.
This layer cause the bolt 'stainless.' Higher levels of chromium and digging in other alloying elements such as molybdenum and nickel enhance this protective barrier and further reduce the corrosion resistance belonging to the stainless steel the best selling grades in hex bolts and nuts, foundation bolts, anchor bolts, bolts & nuts, Nut & bolts in stainless steel being SS 316 and S 316L and 316S31. Customer types of stainless steel fasteners or bolts and nuts, but by far the most common and widely used are the 300 series stainless steels, also known with regards to austenitic stainless steels.
The 300 series designation contains many different compositions of alloy steel bolts and nuts and fasteners (303, 304, 304L, 305, 316, 321, 347, 316S31, 316Letc.) but the common factors among them are:
By far carbohydrates are the next most popular connected with stainless steel bolt and nuts or fasteners or screws, after Type 304, is Type 316. In Type 316 stainless steel bolt and nut & washers or SS 316 Nut and bolt, the chromium content is lowered from 18% to 16%, however, the nickel content is raised to 10% and 2% molybdenum is added into the mixture. This alter in the chromium/nickel ratio and the addition of the molybdenum increases the possible to deal with chlorides. This is the reason Type 316 stainless steel bolt and nut is often used in more corrosive environments where the material will be come across chemical, solvent, or salt water corrosion and makes it the preferred material for marine fabrication. The recent use of 316S31 grade bolt and nut & washers in marine applications and sewage plants and off shore applications in the middle east has enhanced the performance of the bolt and has given a long life to the products life cycle.