Material Reference for Machined Parts
Start from the requirement, not the grade. Pick a function (lightweight, corrosion, high temperature, insulation, wear, food contact and more) and the table filters to the grades that actually deliver it, with density, strength, hardness, modulus, conductivity, service temperature, machinability and a relative cost index in the same row. 48 materials, every column sortable, every value click to copy.
Pick by function
Each card is the reasoning, not just a list: what the function actually needs, where to start, and the failure mode that catches people out. Click a card (or use the dropdown) and the data table below filters to the grades that carry that function.
A grade can carry several functions, and the tags in the table show all of them. Sorting works while a filter is active, so after picking "lightweight" you can sort by tensile strength and see the strongest light alloy at the top.
Material data table
Typical values for the named grade in its common temper, in the sizes a machine shop actually buys. Density, modulus and conductivity are material constants; tensile, yield and hardness depend on temper and section, so treat them as design starting points and let the certificate decide acceptance.
| Material | Class | Density g/cm³ | Tensile MPa | Yield MPa | Hardness | E GPa | k W/(m·K) | Max temp °C | Mach. | Cost index | Functions | Typical machined parts |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 6061-T6变形铝合金 | Aluminum | 2.70 | 310 | 276 | 95 HB | 68.9 | 167 | 150 | B | 1.0 | 轻量化 耐腐蚀 散热导热 低成本量产 尺寸稳定 防静电 | Machine frames, fixtures, housings, heat sinks, brackets, vacuum plates |
| 6082-T6欧标结构铝 | Aluminum | 2.70 | 310 | 260 | 95 HB | 70.0 | 170 | 150 | B | 1.0 | 轻量化 高强度 耐腐蚀 散热导热 | Structural brackets and automation frames to EN standards, machined weldments |
| 7075-T6超高强铝 | Aluminum | 2.81 | 572 | 503 | 150 HB | 71.7 | 130 | 120 | B | 1.8 | 高强度 轻量化 耐磨 | Aircraft fittings, robot links, high load brackets, gearbox and actuator plates |
| 2024-T351硬铝 | Aluminum | 2.78 | 469 | 324 | 120 HB | 73.1 | 121 | 150 | B | 1.7 | 高强度 轻量化 耐高温 | Fatigue loaded fittings and frames, aerospace structural detail parts |
| 5052-H32耐蚀铝镁 | Aluminum | 2.68 | 228 | 193 | 60 HB | 70.3 | 138 | 200 | C | 1.1 | 耐腐蚀 耐化学品 轻量化 食品接触 | Marine and chemical enclosures, tanks, panels, low stress covers |
| 6063-T5挤压铝 | Aluminum | 2.70 | 186 | 145 | 60 HB | 68.9 | 201 | 150 | A | 0.9 | 散热导热 轻量化 低成本量产 | Heat sinks, extrusion based parts, cosmetic and non structural housings |
| MIC-6 cast plate铸造铝板 | Aluminum | 2.68 | 166 | 110 | 65 HB | 71.0 | 121 | 150 | A | 1.3 | 尺寸稳定 散热导热 | Vacuum tables, tooling plates, flat reference plates, machine bed plates |
| 304 / 1.4301奥氏体不锈钢 | Stainless steel | 7.90 | 505 | 215 | 190 HB | 193 | 16.2 | 600 | C | 1.0 | 耐腐蚀 食品接触 医疗生物相容 无磁 耐化学品 | Food machinery, chemical components, medical housings, sanitary fittings |
| 316L / 1.4404含钼超低碳不锈钢 | Stainless steel | 8.00 | 485 | 170 | 180 HB | 193 | 16.3 | 600 | C | 1.4 | 耐腐蚀 医疗生物相容 食品接触 耐化学品 无磁 | Pharmaceutical and marine duty, chlorine and acid exposure, implant tooling |
| 303 / 1.4305易切削不锈钢 | Stainless steel | 7.90 | 620 | 310 | 230 HB | 193 | 16.2 | 400 | A | 1.1 | 耐腐蚀 低成本量产 | High volume turned fittings, connectors, bushings, sensor bodies |
| 17-4PH / 630沉淀硬化不锈钢 | Stainless steel | 7.80 | 1070 | 1000 | 40 HRC | 196 | 17.9 | 300 | C | 2.4 | 高强度 耐腐蚀 医疗生物相容 耐磨 | Aerospace fittings, surgical instruments, valve stems, pump shafts |
| 420马氏体不锈钢 | Stainless steel | 7.75 | 700 | 550 | 52 HRC | 200 | 24.9 | 250 | B | 1.5 | 耐磨 耐腐蚀 医疗生物相容 | Surgical tools, valve trim, wear plates, cutlery grade components |
| 440C高碳马氏体不锈钢 | Stainless steel | 7.70 | 760 | 450 | 58 HRC | 200 | 24.2 | 250 | C | 1.6 | 耐磨 耐腐蚀 医疗生物相容 | Bearings, valve seats, cutting edges, gauges, wear inserts |
| 2205 duplex双相不锈钢 | Stainless steel | 7.80 | 620 | 450 | 290 HB | 200 | 19.0 | 250 | D | 2.2 | 耐腐蚀 高强度 耐化学品 | Chloride and seawater service, chemical pumps, offshore and desalination hardware |
| 1045 / C45中碳调质钢 | Carbon & alloy steel | 7.85 | 600 | 355 | 200 HB | 206 | 51.9 | 400 | B | 0.4 | 高强度 低成本量产 耐磨 | Shafts, studs, spindles, induction hardened journals and wear zones |
| 4140 / 42CrMo铬钼合金钢 | Carbon & alloy steel | 7.85 | 1020 | 655 | 30 HRC | 205 | 42.6 | 400 | B | 0.6 | 高强度 耐磨 耐高温 | Gears, shafts, tie bars, mold bases, high load fasteners, nitrided journals |
| 4340镍铬钼超高强钢 | Carbon & alloy steel | 7.85 | 1110 | 850 | 38 HRC | 205 | 44.5 | 300 | C | 1.1 | 高强度 耐磨 | Aerospace structural detail parts, landing gear class fittings, high stress shafts |
| 20CrMnTi渗碳钢 | Carbon & alloy steel | 7.85 | 1080 | 850 | 60 HRC case | 206 | 43.0 | 200 | B | 0.6 | 耐磨 高强度 低成本量产 | Case hardened gears, splines, pinions, cam and pawl parts |
| 12L14易切削钢 | Carbon & alloy steel | 7.87 | 540 | 415 | 163 HB | 200 | 51.9 | 200 | A | 0.5 | 低成本量产 | High volume turned pins, inserts, hydraulic fittings, non safety spacers |
| Ti-6Al-4V Grade 5钛合金 TC4 | Titanium | 4.43 | 950 | 880 | 35 HRC | 113.8 | 6.7 | 350 | D | 9.0 | 高强度 轻量化 耐腐蚀 医疗生物相容 耐高温 | Aerospace brackets, medical implants and instruments, high speed rotating parts |
| Ti-6Al-4V ELI Grade 23医用钛 ELI | Titanium | 4.43 | 860 | 795 | 32 HRC | 113.8 | 6.7 | 350 | D | 10.0 | 医疗生物相容 耐腐蚀 轻量化 | Implant grade components, surgical instruments, cryogenic hardware |
| Ti Grade 2 (CP)工业纯钛 | Titanium | 4.51 | 344 | 275 | 150 HB | 102.7 | 16.4 | 300 | C | 5.5 | 耐腐蚀 耐化学品 医疗生物相容 轻量化 | Chemical process parts, heat exchanger plates, anodized consumer components |
| C36000易切削黄铜 | Copper alloy | 8.50 | 400 | 310 | 110 HB | 97.0 | 115 | 200 | A | 1.8 | 导电 低成本量产 耐腐蚀 | Connectors, valve bodies, nozzles, threaded fittings, optical adjusters |
| C26000弹壳黄铜 | Copper alloy | 8.53 | 400 | 310 | 130 HB | 110.0 | 120 | 200 | B | 1.7 | 导电 耐腐蚀 | Contacts, terminals, parts that are formed and then machined |
| C11000 ETP紫铜 | Copper alloy | 8.94 | 250 | 150 | 50 HB | 117.0 | 388 | 200 | C | 2.2 | 导电 散热导热 | Bus bars, welding electrodes, thermal straps, RF and vacuum components |
| C93200轴承青铜 | Copper alloy | 8.93 | 240 | 125 | 70 HB | 100.0 | 59 | 200 | B | 1.8 | 低摩擦自润滑 耐磨 耐腐蚀 | Bushings, thrust washers, worm gears, pump bearings, guide sleeves |
| C17200 BeCu铍青铜 | Copper alloy | 8.25 | 1200 | 1000 | 38 HRC | 128.0 | 105 | 200 | C | 14.0 | 导电 高强度 无磁 低摩擦自润滑 | Spring contacts, non sparking tools, high cycle springs (beryllium dust needs control) |
| Inconel 718镍基高温合金 | Nickel alloy | 8.19 | 1300 | 1100 | 40 HRC | 200.0 | 11.4 | 650 | E | 14.0 | 耐高温 高强度 耐腐蚀 | Turbine and exhaust hardware, high temperature fasteners, cryogenic seals |
| Monel 400蒙乃尔合金 | Nickel alloy | 8.80 | 580 | 275 | 150 HB | 179.0 | 21.8 | 480 | C | 11.0 | 耐腐蚀 无磁 耐化学品 | Seawater valves, pump shafts, hydrofluoric acid service, marine fasteners |
| Hastelloy C-276哈氏合金 | Nickel alloy | 8.89 | 790 | 355 | 190 HB | 205.0 | 10.2 | 400 | E | 16.0 | 耐腐蚀 耐化学品 耐高温 | Chemical reactor internals, wet chlorine service, flue gas components |
| Kovar 4J29可伐合金 | Nickel alloy | 8.36 | 520 | 340 | 160 HB | 138.0 | 17.3 | 450 | C | 12.0 | 尺寸稳定 散热导热 | Hermetic glass and ceramic seals, laser and sensor packages, vacuum feedthroughs |
| AZ91D镁合金 | Magnesium | 1.81 | 240 | 150 | 65 HB | 45.0 | 51.0 | 150 | A | 1.2 | 轻量化 散热导热 防静电 | Ultra light housings, handheld device chassis, weight critical brackets |
| ZA-12锌铝合金 | Zinc alloy | 6.03 | 330 | 260 | 105 HB | 96.0 | 113.0 | 150 | A | 0.8 | 低成本量产 低摩擦自润滑 | Bearings, bushings, small precision housings, wear plates |
| POM (Delrin)聚甲醛 | Engineering plastic | 1.41 | 70 | 65 | M84 | 3.1 | 0.31 | 90 | A | 0.8 | 低摩擦自润滑 耐磨 绝缘 低成本量产 尺寸稳定 食品接触 | Gears, bushings, rollers, valve bodies, precision mechanical parts |
| PA6 / PA66尼龙 | Engineering plastic | 1.14 | 80 | 75 | R118 | 3.0 | 0.25 | 90 | B | 0.7 | 低摩擦自润滑 耐磨 绝缘 低成本量产 | Gears, wear pads, rollers, cable guides (moisture uptake changes size) |
| PEEK聚醚醚酮 | Engineering plastic | 1.30 | 100 | 97 | M99 | 3.6 | 0.25 | 250 | C | 20.0 | 耐高温 耐化学品 医疗生物相容 耐磨 绝缘 | Aerospace and semiconductor parts, implant trials, chemical seals, pump components |
| PEEK CF30碳纤增强 PEEK | Engineering plastic | 1.44 | 210 | 200 | M105 | 12.0 | 0.30 | 250 | C | 40.0 | 高强度 耐高温 防静电 耐磨 | High stiffness semiconductor fixtures, structural insulators, wear pads |
| PTFE聚四氟乙烯 | Engineering plastic | 2.20 | 25 | 23 | R58 | 0.7 | 0.25 | 260 | C | 4.5 | 耐化学品 低摩擦自润滑 绝缘 食品接触 耐高温 | Seals, liners, low friction and food contact parts (creeps under load) |
| PVDF聚偏氟乙烯 | Engineering plastic | 1.78 | 55 | 50 | R110 | 2.1 | 0.19 | 150 | B | 5.0 | 耐化学品 绝缘 食品接触 阻燃 | Semiconductor wet bench parts, chemical piping, ultrapure water components |
| PPS聚苯硫醚 | Engineering plastic | 1.35 | 85 | 80 | R123 | 3.8 | 0.29 | 220 | B | 2.5 | 耐高温 耐化学品 阻燃 绝缘 防静电 | Semiconductor tool parts, pump housings, electrical insulators, connectors |
| PEI (Ultem)聚醚酰亚胺 | Engineering plastic | 1.27 | 105 | 100 | M109 | 3.0 | 0.22 | 170 | B | 5.0 | 高强度 耐高温 阻燃 绝缘 医疗生物相容 | Electrical and aircraft interiors, medical trays, amber transparent parts |
| PSU / PPSU聚砜 | Engineering plastic | 1.24 | 75 | 70 | R120 | 2.5 | 0.26 | 160 | B | 2.5 | 耐高温 绝缘 医疗生物相容 耐化学品 | Sterilizable trays, manifolds, sight glasses, repeated autoclave parts |
| PAI (Torlon)聚酰胺酰亚胺 | Engineering plastic | 1.42 | 130 | 110 | M100 | 4.5 | 0.26 | 260 | C | 12.0 | 耐高温 耐磨 低摩擦自润滑 绝缘 | High temperature bearings, wear rings, seal cages, compressor parts |
| PET-P聚对苯二甲酸乙二酯 | Engineering plastic | 1.39 | 80 | 75 | M95 | 3.1 | 0.29 | 100 | A | 1.0 | 耐磨 低摩擦自润滑 低成本量产 食品接触 尺寸稳定 | Wear strips, gears, food contact conveyor parts, precision spacers |
| PC聚碳酸酯 | Engineering plastic | 1.20 | 65 | 60 | M70 | 2.4 | 0.20 | 120 | A | 0.7 | 透明光学 高强度 绝缘 | Lenses, guards, transparent housings, impact resistant covers |
| PMMA有机玻璃 | Engineering plastic | 1.18 | 70 | 65 | M85 | 3.2 | 0.19 | 80 | A | 0.7 | 透明光学 绝缘 低成本量产 | Light guides, optical windows, display parts, machined lenses where finish is enough |
| ABSABS | Engineering plastic | 1.04 | 42 | 38 | R105 | 2.3 | 0.17 | 80 | A | 0.5 | 低成本量产 绝缘 | Enclosures, prototypes, non structural covers, low load spacers |
| HDPE高密度聚乙烯 | Engineering plastic | 0.95 | 30 | 26 | R65 | 1.1 | 0.45 | 80 | A | 0.4 | 耐化学品 低成本量产 绝缘 食品接触 | Tanks, liners, food handling parts, low cost spacers and seals |
Machinability is relative to a well set up CNC process:
A fast with good chip control, easy to hold tolerance
B normal production speeds, predictable
C slower, work hardening or gumming, watch tool wear
D slow, poor chip control, heat and tooling cost
E specialist territory, cutter and strategy decide the result.
Cost index is an indicative material price index with 6061-T6 bar at 1.0, order of magnitude guidance only:
the quoted part price depends on stock size, buy quantity, machining time and finish far more than on the metal.
HB Brinell, HRC Rockwell C, M and R Rockwell M and R for plastics.
Hardness and strength conversion for steels
Carbon and alloy steels per GB/T 1172-1999, 20 to 45 HRC. Useful when a drawing says 40 HRC and the certificate lists HV or HBW, or when estimating tensile strength from a hardness reading.
| HRC | HRA | HV | HBW | Tensile strength carbon steel (MPa) |
|---|---|---|---|---|
| 20 | 60.2 | 226 | 225 | 774 |
| 22 | 61.2 | 235 | 234 | 813 |
| 24 | 62.2 | 247 | 245 | 854 |
| 25 | 62.8 | 253 | 251 | 875 |
| 26 | 63.3 | 259 | 257 | 897 |
| 28 | 64.3 | 273 | 269 | 942 |
| 30 | 65.3 | 288 | 283 | 989 |
| 32 | 66.4 | 304 | 298 | 1039 |
| 34 | 67.4 | 321 | 314 | 1092 |
| 35 | 67.9 | 331 | 323 | 1119 |
| 36 | 68.4 | 340 | 332 | 1147 |
| 38 | 69.5 | 360 | 350 | 1207 |
| 40 | 70.5 | 381 | 370 | 1271 |
| 42 | 71.6 | 404 | 392 | 1340 |
| 44 | 72.6 | 428 | 415 | 1417 |
| 45 | 73.2 | 441 | 428 | 1459 |
| 45.5 | 73.4 | 448 | 435 | 1481 |
| 46 | 73.7 | 454 | 441 | 1503 |
| 46.5 | 73.9 | 461 | 448 | 1526 |
| 47 | 74.2 | 468 | 455 | 1550 |
| 47.5 | 74.5 | 475 | 463 | 1575 |
| 48 | 74.7 | 482 | 470 | 1600 |
| 48.5 | 75 | 489 | 478 | 1626 |
| 49 | 75.3 | 497 | 486 | 1653 |
| 49.5 | 75.5 | 504 | 494 | 1681 |
| 50 | 75.8 | 512 | 502 | 1710 |
| 50.5 | 76.1 | 520 | 510 | - |
| 51 | 76.3 | 527 | 518 | - |
| 51.5 | 76.6 | 535 | 527 | - |
| 52 | 76.9 | 544 | 535 | - |
| 52.5 | 77.1 | 552 | 544 | - |
| 53 | 77.4 | 561 | 552 | - |
| 53.5 | 77.7 | 569 | 561 | - |
| 54 | 77.9 | 578 | 569 | - |
| 54.5 | 78.2 | 587 | 577 | - |
| 55 | 78.5 | 596 | 585 | - |
| 55.5 | 78.7 | 606 | 593 | - |
| 56 | 79 | 615 | 601 | - |
| 56.5 | 79.3 | 625 | 608 | - |
| 57 | 79.5 | 635 | 616 | - |
| 57.5 | 79.8 | 645 | 622 | - |
| 58 | 80.1 | 655 | 628 | - |
| 58.5 | 80.3 | 666 | 634 | - |
| 59 | 80.6 | 676 | 639 | - |
| 59.5 | 80.9 | 687 | 643 | - |
| 60 | 81.2 | 698 | 647 | - |
| 60.5 | 81.4 | 710 | 650 | - |
| 61 | 81.7 | 721 | - | - |
| 61.5 | 82 | 733 | - | - |
| 62 | 82.2 | 745 | - | - |
| 62.5 | 82.5 | 757 | - | - |
| 63 | 82.8 | 770 | - | - |
| 63.5 | 83.1 | 782 | - | - |
| 64 | 83.3 | 795 | - | - |
| 64.5 | 83.6 | 809 | - | - |
| 65 | 83.9 | 822 | - | - |
Valid for carbon and alloy steels per GB/T 1172-1999, 20 to 65 HRC. HBW is tabulated by the standard only to about 60 HRC and tensile strength only to 50 HRC; "-" means the standard does not give a value there. Hardness is not interchangeable between scales: conversions are estimates, the drawing scale governs.
Elastic modulus, shear modulus, Poisson ratio
For deflection estimates, press-fit pressure and thermal-growth sanity checks across the whole range of materials that pass through a machine shop, including the cast irons and polymers that the alloy tables usually leave out.
| Material | E (GPa) | G (GPa) | Poisson ratio |
|---|---|---|---|
| Gray cast iron 灰铸铁 | 118 - 126 | 44.3 | 0.3 |
| Ductile iron 球墨铸铁 | 173 | - | 0.3 |
| Carbon and alloy steel 碳钢合金钢 | 206 | 79.4 | 0.3 |
| Rolled copper 轧制纯铜 | 108 | 39.2 | 0.31 - 0.34 |
| Cold-drawn copper 冷拔纯铜 | 127 | 48.0 | - |
| Rolled phosphor bronze 轧制磷青铜 | 113 | 41.2 | 0.32 - 0.35 |
| Cold-drawn brass 冷拔黄铜 | 89 - 97 | 34.3 - 36.3 | 0.32 - 0.42 |
| Rolled aluminum 轧制铝 | 68 | 25.5 - 26.5 | 0.32 - 0.36 |
| Cast aluminum bronze 铸铝青铜 | 103 | 41.1 | 0.3 |
| Hard aluminum alloy 硬铝合金 | 70 | 26.5 | 0.3 |
| Rolled zinc 轧制锌 | 82 | 31.4 | 0.27 |
| Lead 铅 | 16 | 6.8 | 0.42 |
| Glass 玻璃 | 55 | 1.96 | 0.25 |
| Acrylic 有机玻璃 | 2.35 - 29.42 | - | - |
| Rubber 橡胶 | 0.0078 | - | 0.47 |
| Phenolic laminate 夹布酚醛塑料 | 3.92 - 8.83 | - | - |
| Nylon 1010 尼龙 | 1.07 | - | - |
| Rigid PVC 硬聚氯乙烯 | 3.14 - 3.92 | - | 0.34 - 0.35 |
| PTFE 聚四氟乙烯 | 1.14 - 1.42 | - | - |
| HDPE 低压聚乙烯 | 0.54 - 0.75 | - | - |
How KGL quotes material
Material choice changes three things in a quote: the metal price, the cycle time, and how much inspection the part needs.
| What we do | Why it matters to your price |
|---|---|
| Stock held for the common grades | 6061, 6082, 7075, 304, 316L, 303, 17-4PH, brass, POM, PEEK, PTFE and nylon in bar and plate, so a 1-piece order does not wait for a mill |
| Material certificate with every shipment | Mill certificate traced to the heat number, so your incoming inspection can rely on chemistry and not just dimensions |
| Machinability drives the routing | Free-cutting grades get higher feed and less inspection; titanium and nickel alloys get dedicated cutters, slower passes and more tool changes, which is where the cost sits |
| Grade substitution flagged, never silent | If a drawing calls for a grade outside our standard stock, we quote the grade as written and show the alternative with the trade-off, and you decide |
| Question we hear | Short answer |
|---|---|
| Can you machine 7075 instead of 6061? | Yes, and it holds better finish on thin walls. Expect more per kilo and a little more cycle time, so send the drawing and we will show both. |
| Is 304 good enough or do I need 316L? | If chlorides or a wash-down chemical appear anywhere in service, go 316L. The price difference is small next to a corrosion failure. |
| Which plastic for a machined fixture? | POM for general work, PEEK or PPS if it sees 150 C or semiconductor chemistry, PVDF if it sees aggressive wet chemistry. |
| Can you hit these numbers on titanium? | Yes. See the tolerance page for the bands we hold, and note that titanium moves more in the cut, so we quote the finish passes and the soak schedule in the price. |
Where these grades get machined
Material data decides the process plan. These pages carry the grades we run most, the cut advice that goes with them and the finish that follows.
Machining pages by material family
- Aluminium grades6061, 6082 and 7075: speeds, feeds and where hardness changes the plan.
- Stainless steel grades303, 304, 316L and 17-4PH: work hardening and the heat treatment that follows.
- Titanium gradesGrade 2 and Grade 5: tool life, coolant strategy and stress relief.
- Brass and copper alloysFree-cutting grades for valves, fittings and electrical parts.
Services that run these grades
- CNC millingPrismatic parts in every family listed above.
- CNC turningShafts, bushes and fittings, with the bar stock size that decides the plan.
- 5-axis CNC machiningComplex geometry in hard-to-cut grades, one setup.
What happens after the cut
- Surface treatmentAnodising, passivation, plating and heat treatment, with the size change each one causes.
- Inspection and QCMaterial certificate plus dimensional report on the finished lot.
Have a feature that sits at the edge of one of these bands? Send the drawing and the tolerance question with the drawing and we will answer against it.
Not sure the drawing and the material agree?
Send the 2D and 3D files with the material callout. We return a quote in 24 hours with a straight answer on where the grade, the tolerance and the finish fight each other, and what we would change.