Stainless steel is an alloy that is made up of about 10.5%of chromium content. It is also known as inox or inox metal derived from a French term that is inoxydable. Stainless steel is resistive to corrosion and is widely used in many applications including household and cutlery. One big advantage of stainless steel is that it doesn’t corrode or rust with water plus it doesn’t stain. But its stain-proof property slows down when exposed to the conditions like low oxygen, poor air circulation, and high-salinity.
Many different items are made from stainless steel and angle irons are one of them. Angle iron is an L-shaped material made up of steel to be used for various purposes. Angle irons made from stainless steel are preferred because they are very resistive to corrosion.
They are commonly used for shelves, brackets, frames, bracing, architectural trims and different types of fabrications. Not just this but they are also used in enclosures, tanks, bulkheads, and cabinets. Angles irons are preferred in many industries like paper industry, pulp industry, marine and chemical, food and petrochemical industries. They are mostly preferred where strength and super corrosion resistance is required.
Angle irons mostly come in two types of categories; 304 and 316. They are further divided into 304/304L and 316/316L.
Sizes are classified according to the categories.
304/304L: ¾” x ¾” x 1/8” through 6” x 6” x 3/8” random
316/316L: 1” x 1” x 1/8” through 6” x 6” x 3/8” random
Also known as marine grade stainless steel, they are highly resistive to chlorine attacks and very good in fighting with mild corrosion. Due to the high level of molybdenum and nickel, they are very strong against pitting corrosion. As they have less amount of carbon in them, so their strength against the acidic environment is very good. Very resistive in chloride media and salt water, they are best to be used under water. Their toughness and working properties are very tremendous. Angle irons are durable and long lasting. Excellent resistance to crevice corrosion is another great feature of stainless steel angle irons. 304 series are best known for their toughness whereas 316 have greater resistive properties. They are bad conductors of electricity and are classified as non-magnetic. Their tensile strength is very strong and weldability is excellent.
Reaction to acids, bases, and organics:
They are generally resistive to acids but it also depends on the type of the steel. 316 can resist sulphuric acid at the concentration of 10%or below whereas 304 should never be exposed to sulphuric acid at any concentration. Phosphoric acid is not dangerous for any kind of stainless steel. Hydrochloric acid is very strong and not even 316 should be exposed to it. 304 series is resistive to ammonium hydroxide and so does 316. They are not at all dangerous for the steel. A little higher level that sodium hydroxide is dangerous for 304 when used in high concentration and high temperatures. They can cause cracking and etching. Angle irons of the series 304 should not be exposed to solutions like sodium hypochlorite. 304 and 316 both can handle acetic acids along with a solution of formic acids. Type 3014 is mostly used with formic acid as it discolors the solution. Aldehydes and Amines don’t affect any kind of steel but still, 316 are preferable. Cellulose acid becomes dangerous from 304 types unless the temperature is not raised to a higher level. Fatty acids and fats only effect type 316 at above the temperature of 206 degrees Celsius and type 304 above temperature 150 degrees Celsius. For the processing of urea, type 316L is used.