Have you ever thought about what materials are used for excavator bucket? In this article, we will discuss the most commonly used materials in the pins, sides, cutting edges, housings and teeth of excavator buckets.

Excavator Pins

Excavator pins are usually made of AISI 4130 or 4140 steel. AISI 4000 series steel is chrome molybdenum steel. Chromium improves corrosion resistance and hardening, while molybdenum also improves strength and hardenability.

The first number, 4, represents the grade of the steel and its main alloy composition (in this case, chromium and molybdenum). The second number 1 represents the percentage of alloying elements, which means about 1% chromium and molybdenum (by mass). The last two digits are carbon concentrations in 0.01% increments, so AISI 4130 has 0.30% carbon and AISI 4140 has 0.40%.

The steel used has probably been treated with induction hardening. This heat treatment process produces a hardened surface with wear resistance (58 to 63 Rockwell C) and a malleable interior to improve toughness. Note that bushings are usually made of the same material as pins. Some cheaper pins may be made from AISI 1045. This is a medium carbon steel that can harden.

Excavator Bucket Sides and Cutting Edges

The bucket sides and blade are usually made of AR plate. The most popular classes are the AR360 and AR400. AR 360 is a medium carbon low alloy steel that has been heat treated to provide excellent wear resistance and high impact strength. The AR 400 is also heat treated, but it offers wear resistance and superior yield strength. Both steels are carefully hardened and tempered to achieve the critical product quality of the bucket. Please note that the number after AR is the Brinell hardness of steel.

Excavator Bucket Shell

Bucket housings are usually made from ASTM A572 Grade 50 (sometimes written A-572-50), which is A high strength low alloy steel. The steel is alloyed with niobium and vanadium. Vanadium helps keep steel strong. This grade of steel is ideal for bucket shells as it provides excellent strength while weighing less than comparable steels such as A36. It is also easy to weld and shape.

Excavator Bucket Teeth

In order to discuss what bucket teeth are made of, it is important to understand that there are two ways of making bucket teeth: casting and forging. The cast bucket teeth can be made of low alloy steel with nickel and molybdenum as the main alloying elements. Molybdenum improves the hardenability and strength of steel and can also help reduce some forms of pitting corrosion. Nickel improves strength, toughness and helps prevent corrosion. They may also be made of isothermal quenched ductile iron that has been heat treated to improve wear resistance and impact strength. Forged bucket teeth are also made of heat-treated alloy steel, but the type of steel varies from manufacturer to manufacturer. Heat treatment improves wear performance and increases impact strength.

Conclusion

Excavator buckets are made of several different materials, but all of these materials are of the steel or iron type. The type of material is chosen according to how the part is loaded and manufactured.