{"id":10913,"date":"2020-05-26T12:00:29","date_gmt":"2020-05-26T12:00:29","guid":{"rendered":"https:\/\/www.thermofisher.com\/blog\/metals\/?p=10913"},"modified":"2026-02-05T20:54:10","modified_gmt":"2026-02-05T20:54:10","slug":"cutting-technology-for-knife-blade-metals","status":"publish","type":"post","link":"https:\/\/www.thermofisher.com\/blog\/metals\/cutting-technology-for-knife-blade-metals\/","title":{"rendered":"Cutting Technology for Knife Blade Metals"},"content":{"rendered":"

\"CuttingI recently saw an article published by the World Steel Organization<\/a> about a master Japanese blacksmith who said: \u201cThe quality of a Japanese knife lies in its hardness and strength. Ideally, it\u2019s unbreakable, unbendable, and unchippable, but these qualities conflict with one another.\u201d<\/p>\n

The article talks about how the secret to knife success involves the master-quality craftsmanship and reverence for perfection in even the smallest of details, including the microstructure of the metal itself. \u00a0It was explained that different metals, including steel, have different properties and uses, and craftsmen apply their expertise to bring out the best in their chosen source material.<\/p>\n

For blade crafting, one Japanese knife company uses locally-sourced high-carbon steel that has been specifically formulated for making sharp blades. The blacksmiths there believe the ability of steel to adapt to multiple use cases and its ability to be optimized for the qualities needed, such as rust-resistance, is fascinating. He also believes that there are scientific reasons why a super sharp Japanese blade makes a difference when chefs prepare foods, especially sushi.<\/p>\n

So how can that combination of hardness, strength, and rust-resistance needed for the perfect Japanese knife be attained?\u00a0 It\u2019s all about the alloying \u2013 the combining of two or more metallic elements to enhance metal properties \u2013 and working the metal properly.<\/p>\n

We previously wrote about the difference between metal strength and stiffness.<\/a> A material can have high strength and low stiffness. If a metal cracks easily, it has low strength, but if it has low stiffness, it can deflect a high load.\u00a0 All steel has approximately the same stiffness, but comes in many different strengths depending on the alloying metals used. \u00a0Stainless steel comes in more than 100 grades which are created by adding alloys such as chromium, silicon, nickel, carbon, nitrogen, and manganese to impart properties such as heat resistance, strength, flexibility, and ductility.<\/p>\n

Also, a metal\u2019s properties such as weldability and heat or corrosion resistance depend on the carbon content in steel. Carbon works as a hardening agent. Increasing carbon content increases hardness and strength, but increases brittleness as well.\u00a0 (You can learn more about the metallurgy of steel and its carbon content on\u00a0thefabricator.com<\/em><\/a>.)<\/p>\n

Of course one must get the alloy recipe right, mixing together the precise amount of each element.\u00a0 If not, the quality will suffer, and the product can fail. A steel blade that breaks during use can possibly hurt the user if it snaps off and cuts someone.\u00a0 And a blade that rusts would certainly tarnish a manufacturer\u2019s reputation.<\/p>\n

I\u2019m kind of a knife nerd, or I probably just own too many. Looking in my collection there\u2019s a representation of the most common knife steels, and I\u2019ve noted the typical C% for reference:<\/p>\n