It is a widely employed material in many different applications from medical instruments and storage of chemicals to power generation or transport due to its quality, resistance to corrosion, hygiene, and durability. Although there are more than 3,500 different grades of steel different grades of stainless steel are produced equal.
With so many choices to choose from, how do you make sure that you’re choosing the right grade for your particular requirements?
1. Select the right metal for the Environment in which you operate
To determine which kind of steel is the most durable in the specific setting, consider the conditions that your product will be exposed to. Extremely low pH levels, high tensions, and temperatures, as well as crevice corrosion adversely affect the performance of stainless steel. Steels of the austenitic series, similar to the standard types 316 and304 alloys maintain their toughness, strength, and anti-corrosion properties across the entire temperature range.
Resistance to corrosion is the primary reason to choose the austenitic grade of stainless. Type 316 with molybdenum, is resistant to chloride ions that are found in chemical processing and marine applications. In any steel grade, an excellent design for structural elements is the best protection against corrosion.
2. Make sure you prioritize Strength, Ductility, and Toughness
Then, think about these three mechanical strengths:
- Strength is the amount of stress the metal is able to withstand prior to it breaking or deforms
- Ductility A material’s ability to allow material to be able to be changed in its shape like being stretched out of the form of a thread or wire without losing the strength or breaking
- Toughness Metal’s capability to absorb and deform prior to breaking
Stainless steel is composed of 10-30% chromium, which is an alloying component, which helps to resist corrosion. The addition of nickel in austenitic grades gives the most ductility and toughness in stainless grades. The grades with the highest concentration of chromium-molybdenum and nickel are the ones that are most resistant to corrosion.
The content of the alloy isn’t the only thing to be considered when selecting a quality of stainless steel. processing of the material also impacts the mechanical properties. The amount of time it is kept at various temperatures in the cooling process, and the speed of cooling will affect the quality of the steel overall.
The carbon steels’ hardness is increased with the process of heat treating, Austenitic steel is made harder by cold work like bending, rolling, or swaging at temperatures lower than the temperature of recrystallization. Take note of the fact that increasing the degree of hardness through cold-working operations can decrease other properties, such as elongation and resistance to impact.
3. Process and Form
Austenitic stainless steel is available in wire, bar tubes, pipes sheets, and plate forms. It is common for these products to require additional shaping or machining before they are able to be utilized for their particular purpose.
Tubes made of stainless steel can, for example, require bending or coiling or redrawing, machining, welding, or even end form. In the event that your stainless can undergo machining processes such as CNC drilling, machining, bevel cutting, reaming grinding, knurling, or threading, select a machining speed that minimizes the possibility of hardening during work or choose the “free machine” grade that contains sulfur.
When welding stainless steel component embrittlement in the welding region is the most serious issue. Select lower carbon steel such as 304,304L, or 316L, to lessen the risk of the formation of carbide.
4. Be aware of the preferences of your customers
Many designers select stainless steel due to its attractive appearance, whether that is a glossy electropolished “bright” finish or an uninteresting “pickled” finish or a matte surface that has been polished to a particular RMS or a black, light-absorbing oxide coating. Austenitic stainless steel is able to take all of them, plus the more common use of passivation.
Customers might also require certification to meet specific specifications for their applications. For example, ASTM A213 and A249 are suitable to make boiler, superheater, and heat exchanger tubes, whereas ASTM A908 is recommended for austenitic stainless steel that has been drawn hard tube for use in industrial applications. The ASTM standards are roughly 12,000 in number. ASTM standards and each one addresses a specific requirement to ensure that customers are aware of the technical standards that are tested on chemical properties, heat treatments, temper, as well as other mechanical and physical characteristics.
5. Control the cost of materials and ensure availability
While the most durable austenitic stainless steels are some of the most expensive stainless steels on the front, they are worth the cost. Picking corrosion-resistant steel that is suitable for its purpose can cut down on maintenance and downtime as well as the cost of replacement. Costing for life cycles can be quantified using methods that determine the future and present expenses and produce an “apples-to-apples” comparison of various materials.