Stainless steel is a commonly used material in many industries and applications owing to its exceptional properties. Two of the most popular grades of stainless steel used are 18-8 and Grade 8. While they may sound similar, they differ significantly in composition, properties, and functionality. In this blog post, we will explore the differences between stainless steel 18-8 and grade 8 and help you understand which one to use.
Difference Between Stainless Steel 18-8 vs Grade 8
Chemical Composition:
Stainless Steel 18-8 is Type 304, containing 18 percent chromium and 8 percent nickel. Grade 8 stainless steel, on the other hand, is a high-strength alloy that contains 8 per cent nickel and 18 per cent chromium, along with other trace elements like molybdenum, vanadium, and titanium. The primary difference between the two is the presence of other trace elements that give Grade 8 high-strength properties.
Strength and Durability:
Grade 8 stainless steel has a higher tensile strength than 18-8 and is known for its exceptional durability, strength, and toughness. It is commonly used in hardware and construction applications where strength and load-bearing capacity are critical factors. Stainless Steel 18-8, on the other hand, is a low-strength alloy with good corrosion resistance properties and is commonly used in applications where strength is not a primary concern.
Corrosion Resistance:
Both grades of stainless steel are highly corrosion-resistant but differ in their resistance to certain types of acids and chemicals. Stainless Steel 18-8 is resistant to most organic and inorganic chemicals, while Grade 8 is more resistant to certain acids that can cause pitting and corrosion. However, both grades are highly resistant to oxidation and can withstand exposure to high temperatures, making them ideal for high-temperature applications.
Cost:
Stainless Steel 18-8 is more cost-effective than Grade 8, owing to its lower strength properties and simpler composition. Grade 8 is more expensive due to its added strength and durability properties, making it ideal for use in high-stress applications such as nuts, bolts, and screws that require constant load-bearing capacity.
Applications:
Stainless Steel 18-8 is commonly used in household and commercial applications such as cookware, cutlery, and kitchen appliances, owing to its excellent corrosion resistance properties. It is also used in construction and automotive applications where strength is not a primary concern. Grade 8, conversely, is commonly used to manufacture high-stress hardware and equipment such as aircraft parts, automotive components, and precision instruments.
Conclusion:
Stainless Steel 18-8 and Grade 8 are two of the most commonly used grades of stainless steel, but their properties and applications differ significantly. Depending on your specific needs and requirements, choose the grade of stainless steel that best suits your application. Stainless Steel 18-8 is ideal for applications that require excellent corrosion resistance but do not require high-strength properties, while Grade 8 is best suited for high-stress applications that require exceptional durability and strength. So, carefully consider all the factors before choosing the right grade of stainless steel for your project.
