Steel

1. Carbon Steel：
   (1) Low Carbon Steel： Generally features good toughness, low hardness, and excellent machinability. With a carbon content below 0.25%, it is commonly used for general hardware components.
   (2) Medium Carbon Steel： Offers a balanced combination of strength and toughness, with carbon content ranging from 0.25% to 0.6%. It is widely applied in machinery parts, shafts, and mechanical components.
   (3) High Carbon Steel： Contains the highest carbon content among carbon steels (0.6%–2%), resulting in superior hardness and strength. Although there are many subcategories within high carbon steel, it is most commonly used for blades, cutting tools, and springs.
2. Alloy Steel： Alloy steel is produced by adding elements such as chromium, molybdenum, and nickel to enhance strength, toughness, and wear resistance. Its applications are highly diverse, including gears, crankshafts, drive shafts, and mold components.
3. Tool Steel： High-Speed Steel (HSS) is the most widely used. Its key characteristics include high hardness and excellent wear resistance, maintaining cutting performance even at elevated temperatures.

Stainless

Also known as “white iron” in Chinese, it is widely used in food machinery components, medical devices, and equipment parts. One of its key characteristics is its non-magnetic or very weakly magnetic property, which makes it particularly suitable for applications in the medical and aerospace industries. Stainless steel includes many different grades; the following summarizes the most commonly used series in the machining industry:

• 201 Series： An economical option but more prone to rust. Commonly used in window frames, doors, and general structural components.
• 304 Series： The most widely used stainless steel grade. When referring to “white iron,” it typically means 304. It is a food-grade stainless steel with excellent corrosion resistance, making it widely applied in kitchen equipment, utensils, home appliances, construction materials, and various industries.
• 316 Series： Known as medical-grade stainless steel. It contains added molybdenum (Mo), giving it superior corrosion resistance compared to 304. Although more costly, it is commonly used in coastal industrial equipment, the medical field, and is increasingly adopted in food-related applications due to rising safety and hygiene standards.
• 430 Series： A more cost-effective grade compared to 304 and 316, with better resistance to nitric acid corrosion. It is frequently used in automotive components as well as kitchenware, dishwashers, and washing machine interiors.

Aluminum Alloy

Aluminum alloy is lightweight, offers excellent thermal conductivity, is easy to machine, and is fully recyclable. It is widely used in the sports equipment and bicycle industries, making it one of the most common materials on the market.

Copper Alloy

Pure copper offers excellent ductility, electrical conductivity, and thermal conductivity. Because of these properties, it is widely used in electronic components, construction materials, and the electrical wiring and cable industries.

Titanium Alloy

Titanium features high strength, light weight, and excellent corrosion resistance. It was originally used in aerospace applications such as aircraft engines and structural components. With advancements in material technology, titanium is now widely used in medical implants, bicycle components, automotive parts, and even high-end watch components.