Grade / Alloy | Typical Temper / Standard | Key Characteristics | Typical Applications |
6061 | T6 / T651 | Good machinability, balanced strength and corrosion resistance | Housings, brackets, fixtures, machine components |
6082 | T6 / T651 | Higher-strength structural alloy; widely used in Europe | Structural parts, frames, machine components |
7075 | T6 | High strength-to-weight ratio and good machinability | Aerospace parts, high-load components, precision fixtures |
2024 | T3 / T4 | High strength and good fatigue resistance | Aerospace and mechanical components |
5052 | H32 / H34 | Good formability and corrosion resistance | Sheet-metal parts, covers, enclosures |
5754 | H22 / H32 | Good formability and weldability | Sheet metal, tanks, general fabrication |
Machining stress and clamping force can affect thin-wall parts. Appropriate workholding and machining sequences help maintain dimensional stability.
Critical dimensions are controlled through process planning and appropriate inspection methods, including CMM inspection when required.
Tool selection and cutting parameters are optimized according to cosmetic and functional surface requirements.
For tightly toleranced anodized parts, coating thickness and dimensional build-up should be considered before final machining dimensions are established.
Grade / Alloy | Typical Temper / Standard | Key Characteristics | Typical Applications |
1018 | ASTM A108 / equivalent | Good machinability and weldability; low carbon | General parts, shafts, brackets, fixtures |
1045 | ASTM A108 / equivalent | Higher strength and hardness than 1018 | Shafts, gears, machine components |
A36 | ASTM A36 | Good weldability and formability | Structural parts, frames, base plates |
1020 | ASTM A108 / equivalent | Good machinability and weldability | Pins, bushings, general parts |
4140* | ASTM A29 / equivalent | Higher strength and toughness; alloy steel rather than plain carbon steel | Shafts, gears, high-load components |
Confirm grade, delivery condition and any material certification before production.
Where heat treatment is required, machining allowance and final finishing should be planned around dimensional change.
Machining parameters and finishing processes are selected according to functional and cosmetic requirements.
Stress, heat treatment and material removal sequence should be considered for long, thin or precision parts.
Grade / Alloy | Typical Temper / Standard | Key Characteristics | Typical Applications |
304 / 304L | ASTM A276 / A479 depending on product form | General-purpose corrosion resistance and good formability | Equipment parts, housings, brackets, food-related components |
316 / 316L | ASTM A276 / A479 depending on product form | Improved chloride and chemical corrosion resistance | Marine, chemical, medical, food and process equipment |
303 | ASTM A582 | Free-machining stainless with improved machinability | Precision turned parts, fasteners, fittings |
17-4PH | ASTM A564 | Precipitation-hardening stainless; high strength | Aerospace, high-load components, shafts |
420 | ASTM A276 | Martensitic stainless; can be hardened | Shafts, blades, mechanical components |
Stainless work-hardens easily; rigid tooling and suitable cutting parameters are important.
Heat should be controlled to protect dimensional accuracy and tool life.
Surface requirements may include polishing, passivation or controlled machining finish.
Material grade and post-processing should match the actual service environment.
Grade / Alloy | Typical Temper / Standard | Key Characteristics | Typical Applications |
4140 / 42CrMo4 | ASTM A29 / EN 10083 | High strength, good toughness and heat-treat response | Shafts, gears, fixtures, mechanical components |
4340 / EN24 | ASTM A29 / BS 970 equivalent | Very high strength and toughness | Axles, shafts, drivetrain and high-load components |
8620 | ASTM A29 | Good carburizing response and tough core | Gears, shafts, bushings |
16MnCr5 | EN 10084 | Case-hardening steel with good core toughness | Gears, shafts, transmission parts |
52100 / 100Cr6 | ASTM A295 / EN ISO 683-17 | High hardness and wear resistance after heat treatment | Bearings, rollers, wear components |
D2 | ASTM A681 | High wear resistance; tool steel | Cutting tools, dies, wear tooling |
Plan rough machining, heat treatment and finish machining/grinding in the correct sequence.
Heat treatment and asymmetric material removal can cause distortion; machining allowance may be required.
Hardened critical surfaces may require grinding to achieve final tolerance and finish.
Machining strategy should reflect hardness, wear requirements and final functional surfaces.
Grade / Alloy | Typical Temper / Standard | Key Characteristics | Typical Applications |
C36000 | ASTM B16 | Free-machining brass with excellent machinability | Connectors, fittings, valves, precision turned parts |
C26000 | ASTM B36 | Good ductility and formability | Electrical and formed components |
C46400 | ASTM B21 / B124 depending on form | Naval brass with improved seawater corrosion resistance | Marine components, hardware |
C38500 | ASTM B455 / relevant product standard | Good machinability and hot-working properties | Architectural and machined components |
H62 / H59 | GB grades | Common Chinese brass grades; properties depend on exact specification | General machined components; use only when customer specification permits |
Cutting parameters should support clean chip evacuation and stable production.
Sharp tools help maintain dimensional accuracy and surface quality.
Thermal effects, tool wear and workholding should be controlled for tight tolerances.
Brass can achieve good machined appearance and can also be polished or plated.
Grade / Alloy | Typical Temper / Standard | Key Characteristics | Typical Applications |
POM / Acetal | Delrin-type acetal where specified | Good dimensional stability, low friction and machinability | Gears, bushings, precision mechanical parts |
PA6 / PA66 | Nylon | Good toughness and wear resistance; moisture absorption must be considered | Bushings, rollers, mechanical components |
PC | Polycarbonate | High impact resistance and good dimensional properties | Covers, guards, transparent or mechanical components |
PEEK | High-performance thermoplastic | High temperature, chemical and wear resistance | Semiconductor, medical, aerospace and demanding industrial parts |
PTFE | Fluoropolymer | Very low friction and excellent chemical resistance; relatively soft | Seals, insulators, low-friction components |
UHMW-PE | Ultra-high-molecular-weight polyethylene | Excellent abrasion resistance and low friction | Wear strips, guides, rollers, food/packaging equipment where grade is suitable |
Moisture absorption, thermal expansion and internal stress can affect dimensions depending on plastic type.
Excessive cutting heat can soften or distort thermoplastics; cutting strategy should minimize heat buildup.
Workholding and machining sequence should avoid excessive clamping force and deformation.
Tool geometry and cutting parameters should match the specific plastic and cosmetic/functional requirements.
| Process | Effect | Notes |
|---|---|---|
| Anodizing | Forms a hard protective oxide film, available in multiple colors, improves wear resistance & corrosion resistance. | Mainly applicable to aluminum alloys; dimensional tolerance will slightly change. |
| Powder Coating | Thick uniform coating, excellent anti-corrosion performance, rich color options. | Higher coating thickness; small precision threads need protection. |
| Electroplating | Metal coating on workpiece surface, enhance hardness, conductivity and rust resistance. | Suitable for steel, brass; material compatibility needs verification in advance. |
| Passivation | Creates dense passive film, greatly improve anti-rust performance without changing appearance. | Commonly used for stainless steel; no obvious thickness increase. |
| Black Oxide | Uniform matte black surface, slight anti-corrosion property, good decorative effect. | No abrasion resistance; usually matched with anti-rust oil. |
| Polishing | Achieve smooth, glossy surface, reduce surface friction. | Can remove minor tool marks; tight tolerance parts need process evaluation. |
| Sandblasting | Uniform matte texture, eliminate machining traces, improve coating adhesion. | Will slightly remove surface material, affect final dimension. |
| Process | Applicable Materials | Property Changes | Key Advantages |
|---|---|---|---|
| Annealing | Carbon steel, alloy steel, stainless steel, non-ferrous metals | Reduces material hardness, improves machinability; eliminates internal stress, refines grains, homogenizes structure | Good structural stability, reduces deformation in subsequent processing; optimizes mechanical properties and prepares for final heat treatment |
| Quenching & Tempering | Medium carbon steel, medium carbon alloy steel (e.g. 45#, 40Cr) | Obtains uniform tempered sorbite structure, combining high strength, high plasticity and high toughness | Excellent comprehensive mechanical properties, can withstand large loads and impacts, core heat treatment process for structural parts |
| Quenching | Carbon steel, alloy steel, tool steel | Greatly improves material hardness, wear resistance and strength, obtains martensite/bainite structure | High surface hardness, strong wear resistance, meets the requirements of high wear resistance and high load-bearing of parts |
| Carburizing | Low carbon steel, low carbon alloy steel | Surface carbon content increased, high hardness and wear resistance after quenching, while the core maintains the toughness of low carbon steel | Achieves the performance matching of hard surface and tough core, which not only ensures surface wear resistance, but also avoids overall brittle fracture of parts |
| Nitriding | Alloy steel, stainless steel, cast iron | Forms high hardness nitride layer on the surface, with hardness far exceeding quenching, improves corrosion resistance and fatigue strength | Low treatment temperature, minimal part deformation; high surface hardness, wear and corrosion resistance, no need for subsequent quenching |
| Polishing | All kinds of machinable materials such as metals and plastics | Greatly reduces surface roughness, obtains smooth mirror/matte effect, reduces friction coefficient | Can remove tool marks and scratches, improve surface finish and assembly fit, optimize appearance texture |
| Sandblasting | All kinds of metals, hard plastics | Forms uniform matte/rough texture on the surface, removes oxide scale, burrs and processing marks | Enhances coating adhesion, unifies product appearance texture; can adjust abrasive grain size to control surface roughness |
