Stainless steel is generally not considered the ideal choice for creating a functional katana due to its properties and characteristics. While stainless steel offers excellent corrosion resistance, it has limitations when it comes to the specific requirements of a katana.

Here are a few reasons why stainless steel may not be as suitable for a functional katana:

1. Hardness and Edge Retention: Stainless steel tends to be harder to sharpen and has lower edge retention compared to high-carbon steel. A functional katana requires a sharp, durable edge that can withstand repeated cutting and maintain its sharpness over time.
2. Flexibility and Toughness: Stainless steel is often tougher and more flexible than high-carbon steel, which can result in a blade that is less stiff or springy. A katana blade needs to have a balance of hardness, flexibility, and resilience to absorb impact and maintain its shape during cutting.
3. Historical Authenticity: If you are seeking a katana with historical authenticity or wish to replicate traditional craftsmanship, stainless steel is not the traditional material used in traditional katana blades. High-carbon steel, with its specific properties and forging techniques, is preferred for traditional and functional katana.

While stainless steel may have some advantages in terms of corrosion resistance and low maintenance, it is generally recommended for decorative or display purposes rather than for functional use in cutting or martial arts practice.

If you are considering acquiring a functional katana, it is advisable to seek one made from traditional high-carbon steel, crafted by skilled swordsmiths who follow traditional forging methods. These blades are designed specifically for performance, balance, and durability, aligning with the historical and cultural significance of the katana.