Local concepts: Local concepts: Chrome equivalent: 1. Chromium Equivalent: The element that constitutes ferrite in the relationship between the stainless steel composition and the structure is converted to the sum of Cr elements (having an interaction coefficient of Cr of 1) according to the level of the effect, which is called Cr equivalent.

2. Nickel Equivalents: The composition of austenitic elements in the composition of the stainless steel and the relationship between the elements is converted to the sum of Ni elements (in terms of nickel equivalent: Ni's coefficient of action is 1), which is called Ni equivalent. .

3. The brittleness of 4750C embrittled high-chromium ferritic stainless steel in the range of 400~540 degrees will appear brittle, because its most sensitive temperature is embrittlement: 475 degrees is near, so it is called brittleness of 475 degrees. The strength and hardness are added, while the plasticity and toughness are clearly reduced.

4. Condensation Form: The condensation form first refers to the type of primary phase (γ or δ) that promotes the condensation process at the end of the crystallization, followed by the phase in which the coagulation form is completed: Condensation Form Solid process.