Difference Between Surgical Steel and Stainless Steel

Main Difference – Surgical Steel vs Stainless Steel

Stainless steel is a type of steel made by adding chromium to a metal alloy. The purpose of mixing chromium is to prevent iron from oxidizing and rusting. Surgical steel is a grade of stainless steel, which includes steel used for biomedical applications. The main difference between surgical steel and stainless steel is that surgical steel has only biomedical applications whereas stainless steel has many different applications.

Key Areas Covered

1. What is Surgical Steel
      – Definition, Application
2. What is Stainless Steel
      – Definition, Different Types
3. What is the Difference Between Surgical Steel and Stainless Steel
      – Comparison of Key Differences

Key Terms: Austenitic Stainless Steel, Duplex Stainless Steel, Ferritic Stainless Steel, Martensitic Stainless Steel, Metal Alloy, Molybdenum, Rusting, Stainless Steel, Steel, Surgical Steel

What is Surgical Steel

Surgical steel is a type of stainless steel that is used to produce only items required for surgeries. It is a grade of stainless steel that has biomedical applications. There are several different types of stainless steel available depending on the chemical composition. Among these types, austenitic and martensitic are used as surgical steel.

Figure 1: Surgical stainless steel is used to produce surgical items.

The most common types of surgical stainless steel are composed of about 2-3% of molybdenum. This is helpful in resistance to corrosion. This steel can be used both in industries and in surgeries.

Austenitic is the most weld-able stainless steel. It contributes to the largest portion of stainless steel in the steel market. Martensitic steel is another type of stainless steel which has about 20% of chromium.

What is Stainless Steel

Stainless steel is a type of steel which is composed of iron and chromium. It is considered as a metal alloy. It has about 10% of chromium mixed with iron. The other metal elements present in stainless steel are nickel, molybdenum, titanium, and copper. Non-metal additions mainly include carbon. 

The purpose of mixing chromium is to prevent iron from oxidizing. This avoids rusting of steel and gives a corrosion resistance property to Steel. Chromium makes an oxidized layer on the surface of the steel, which is called “passive layer.” This prevents iron from oxidation. However, it is not fully resistant to corrosion, especially in conditions like high concentrated salt water.

Since two metals are mixed together, stainless steel is very strong. But it is expensive when compared to other types of steel. In order to mix the two metals, it is essential that the metals should be in the molten state. Otherwise, a uniform mixing would not occur. Then steel is left to cool and harden. Later, the surface of the stainless steel is washed with an acid in order to remove any impurity.

Figure 2: Kitchen items are made of stainless steel.

The most desired property of stainless steel is its corrosion resistance. Unlike normal steel, it does not undergo corrosion; therefore, rusting is absent. This property makes it useful in the production of kitchen and healthcare products because it is safe to be used in moist environments. It also has a high heat resistance, making it suitable for the production of kitchen items. Stainless steel has a more attractive appearance than normal steel. According to their properties, stainless steel is also divided into sub-groups as follows.

• Duplex stainless steel
• Martensitic stainless steel
• Ferritic stainless steel
• Austenitic stainless steel

Austenitic stainless steel is the most weld-able stainless steel. It contributes to the largest portion of the stainless steel in the steel market. Ferritic stainless steel is composed of trace amounts of nickel, chromium, and carbon. This steel has good ductility and malleability. Martensitic stainless steel is another type of stainless steel which has about 20% of chromium. Duplex stainless steel is mostly used in piping applications.

Difference Between Surgical Steel and Stainless Steel

Definition

Surgical Steel: Surgical steel is a type of stainless steel that is used to produce items required for surgeries.

Stainless Steel: Stainless steel is a type of steel which is composed of iron and chromium.

Application

Surgical Steel: Surgical steel has only biomedical applications.

Stainless Steel: Stainless steel has many applications including production of kitchen items, etc.

Types

Surgical Steel: Surgical steel includes austenitic stainless steel and martensitic stainless steel.

Stainless Steel: Stainless steel is available in different types as duplex, martensitic, ferritic and austenitic.

Conclusion

Surgical steel is a type of stainless steel. The main difference between surgical steel and stainless steel is that surgical steel has only biomedical applications whereas stainless steel has many different applications.

References:

1. “Surgical Steel and Hypoallergenic Metals.” Rings and Things, Available here.
2. “Stainless steel.” Wikipedia, Wikimedia Foundation, 21 Nov. 2017, Available here.

Image Courtesy:

1. “Pinza emostatica e portaghi” By Ricce – Own work (Public Domain) via Commons Wikimedia
2. “1839061” (Public Domain) via Pixabay