Type 201 Stainless Steel is an austenitic chromium-nickel-manganese stainless steel which was developed to conserve nickel. Type 201 is a lower cost alternative to conventional Cr-Ni stainless steels such as 301 and 304. Nickel is replaced by additions of manganese and nitrogen. It is non-hardenable by thermal treatment, but may be cold worked to high tensile strengths. Type 201 is essentially nonmagnetic in the annealed condition and becomes magnetic when cold worked. Type 201 can be substituted for Type 301 in many applications.

Grade 304 stainless steel is generally regarded as the most common austenitic stainless steel. It contains high nickel content that is typically between 8 and 10.5 percent by weight and a high amount of chromium at approximately 18 to 20 percent by weight. Other major alloying elements include manganese, silicon, and carbon. The remainder of the chemical composition is primarily iron.

The high amounts of chromium and nickel give 304 stainless steel excellent corrosion resistance. Common applications of 304 stainless steel include:

• Appliances such as refrigerators and dishwashers
• Commercial food processing equipment
• Fasteners
• Piping
• Heat exchangers
• Structures in environments that would corrode standard carbon steel.

与 304 类似，316 级不锈钢含有大量的铬和镍。316 还含有硅、锰和碳，其中大部分成分是铁。304 和 316 不锈钢的主要区别在于化学成分，316 含有大量的钼；通常按重量计 2% 到 3%，而 304 中只有痕量。较高的钼含量导致 316 级具有更高的耐腐蚀性。

在为海洋应用选择奥氏体不锈钢时，316 不锈钢通常被认为是最合适的选择之一。316 不锈钢的其他常见应用包括：

• 化学加工和储存设备。
• 炼油设备
• 医疗设备
• 海洋环境，尤其是存在氯化物的海洋环境