Generally speaking, the commonly used materials for precision machining are divided into two categories:
Processing of metal materials. Processing of non-metallic materials (such as ceramics, plastics, etc.)
Hardness from high to low: stainless steel>cast iron>copper>aluminum
Let's talk about some commonly used ones, hoping they will be useful to you:
1. 45- High quality carbon structural steel, which is the most commonly used medium carbon quenched and tempered steel.
Main features: The most commonly used medium carbon quenched and tempered steel has good comprehensive mechanical properties, low hardenability, and is prone to cracking during water quenching. Small parts should be treated with quenching and tempering, while large parts should be treated with normalizing.
Application example: mainly used for manufacturing high-strength moving parts, such as turbine impellers and compressor pistons. Shafts, gears, racks, worms, etc. Pay attention to preheating before welding and stress relieving annealing after welding.
2. Q235A (A3 steel) - The most commonly used carbon structural steel.
Main features: high plasticity, toughness, welding performance, cold stamping performance, as well as certain strength and good cold bending performance.
Application example: widely used for general requirements of parts and welded structures. Such as tension rods, connecting rods, pins, shafts, screws, nuts, collars, brackets, frames, building structures, bridges, etc. that are not subjected to significant force.
3. 40Cr - One of the most widely used steel types, belonging to alloy structural steel.
Main features: After quenching and tempering treatment, it has good comprehensive mechanical properties, low-temperature impact toughness, and low notch sensitivity. It has good hardenability, and can achieve high fatigue strength when oil cooled. Parts with complex shapes are prone to cracks when water cooled, with moderate cold bending plasticity. After tempering or quenching, it has good machinability, but poor weldability and is prone to cracks. It should be preheated to 100-150 ℃ before welding, and is generally used in the quenched and tempered state, Carbonitriding and high-frequency surface quenching treatment can also be carried out.
Application example: After quenching and tempering treatment, it is used to manufacture parts with medium speed and medium load, such as machine tool gears, shafts, worms, spline shafts, thimble sleeves, etc. After quenching and high-frequency surface quenching, it is used to manufacture parts with high surface hardness and wear resistance, such as gears, shafts, spindles, crankshafts, mandrels, sleeves, pins, connecting rods, screws and nuts, intake valves, etc. After quenching and medium temperature tempering, it is used to manufacture parts with heavy load and medium speed impact, such as oil pump rotors Sliders, gears, spindles, collars, etc., after quenching and low-temperature tempering, are used to manufacture heavy-duty, low impact, and wear-resistant parts, such as worms, spindles, shafts, collars, etc. The carbon nitrogen co infiltration area is used to manufacture transmission parts with larger dimensions and higher low-temperature impact toughness, such as shafts, gears, etc. 4. HT150- Grey cast iron
Application examples: gear box, machine bed, box, hydraulic cylinder, pump body, valve body, flywheel, cylinder head, pulley, bearing cover, etc
5. 35- Common materials for various standard parts and fasteners
Main features: appropriate strength, good plasticity, high cold plasticity, and acceptable weldability. Under cold conditions, local upsetting and wire drawing can be carried out. Low hardenability, used after normalizing or tempering
Application example: Suitable for manufacturing small cross-section parts that can withstand large loads, such as crankshafts, levers, connecting rods, shackles, and various standard parts and fasteners
6. 65Mn - commonly used spring steel
Application examples: various small-sized flat and round springs, seat cushion springs, spring springs, as well as spring rings, valve springs, clutch springs, brake springs, cold coil coil springs, snap springs, etc. can also be made.
7. 0Cr18Ni9- the most commonly used stainless steel (American grade 304, Japanese grade SUS304)
Characteristics and applications: As a stainless and heat-resistant steel, it is widely used, such as food equipment, general chemical equipment, and industrial equipment
8. Cr12- Commonly used cold work mold steel (American steel grade D3, Japanese steel grade SKD1)
Characteristics and application: Cr12 steel is a widely used cold work die steel, which belongs to high carbon and high chromium ledeburite steel. This steel has good hardenability and good wear resistance; Due to the high carbon content of 2.3% in Cr12 steel, its impact toughness is poor, it is prone to brittle cracking, and uneven eutectic carbides are easily formed;
Cr12 steel, due to its excellent wear resistance, is often used in the manufacturing of cold stamping dies, punches, cutting dies, cold heading dies, cold extrusion dies with high wear resistance, such as punches and dies, drill sleeves, gauges, wire drawing dies, stamping dies, wire drawing plates, deep drawing dies, and powder metallurgy cold pressing dies with low impact loads
9. DC53- Commonly Used Cold Working Die Steel Imported from Japan
Characteristics and Application: High strength and toughness cold work mold steel, steel grade from Japanese Datong Special Steel (Zhuzhou) manufacturer. After high-temperature tempering, it has high hardness, high toughness, and good wire cutting performance. Used for precision cold stamping dies, drawing dies, thread rolling dies, cold punching dies, punches, etc
10. SM45- Ordinary carbon plastic mold steel (Japanese steel grade S45C)