表面処理リファレンス
まず機能要求、処理名ではありません。耐食、耐摩耗、低摩擦、アース、絶縁、色、硬化、疲労、衛生、高温です。処理 28 種について、膜厚、硬さ、耐食性、導電性への影響、外観、生じる寸法変化、使用温度、根拠となる規格を掲載します。あわせて Ra と Rz の系列と、各加工法が実際に保てる水準も示します。
14 の要求処理 28 種片側の寸法変化値をクリックでコピー「/」で検索
要求から選ぶ
表面処理はまず機能の判断で、見た目はその次です。各カードは、その要求が本当に必要とするもの、どこから試すか、 経験上見落とされやすい不具合をまとめています。カードをクリックするか選択欄を使うと、下の処理表がその要求を満たすものに絞り込まれます。
設計者が意外に思うのが寸法変化の列です。陽極酸化、めっき、粉体塗装、窒化は寸法を動かします。 一方、不動態化、クロメート、PVD、レーザーマーキングはほとんど寸法を変えません。
処理法データ表
実務での代表的な範囲です。膜厚、硬さ、耐食性の値は処理規格と取引先の実務に基づきます。 お客様の部品での正確な値は注文時に取り決め、適合証明書で証明します。
| 処理 | 系統 | 母材 | 膜厚 | 硬さと耐摩耗 | 耐食性 | 導電性への影響 | 外観 | 片側の寸法変化 | 最高温度 °C | 機能 | 規格 | 代表部品 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Anodize, Type II硫酸阳极氧化 | Anodizing | Aluminum | 5 - 25 um | 200 - 400 HV oxide; hard but brittle and chips at sharp edges | 300 - 500 h salt spray when sealed | Insulating, breakdown about 20 - 30 V per um | Clear, dyed black or any colour, satin to semi gloss | About half grows outward: roughly +10 um per side at a 20 um layer | 150 | 耐腐蚀防护 外观装饰 电绝缘 | MIL-A-8625 Type II, ISO 7599, GB/T 8013.1 | Enclosures, brackets, cosmetic panels, instrument and camera housings |
| Hard anodize, Type III硬质阳极氧化 | Anodizing | Aluminum | 25 - 60 um, up to 100 um | 350 - 500 HV; the wear answer on aluminium | 500 - 1000 h salt spray when sealed | Insulating, same order as Type II | Dark grey to bronze or black, matte | About half grows outward: +15 to +30 um per side | 200 | 耐磨 耐腐蚀防护 电绝缘 低摩擦脱模 | MIL-A-8625 Type III, GB/T 8013.1 | Hydraulic cylinder bores, valve bodies, wear plates, sliding and pneumatic surfaces |
| Anodize, chromic Type I铬酸阳极氧化 | Anodizing | Aluminum | 2 - 7 um | Thin, minimal fatigue penalty, not a wear layer | 200 - 336 h salt spray | Insulating | Grey green to clear | Half outward: +1 to +3 um per side | 150 | 耐腐蚀防护 疲劳寿命 | MIL-A-8625 Type I and IB, AMS 2470 | Aerospace structural parts where fatigue life must be preserved, bonded and riveted assemblies |
| Electroless nickel, Ni-P化学镀镍 | Plating, electroless | Steel, stainless, copper, aluminium with zincate | 5 - 50 um | 500 - 700 HV as plated; 900 - 1000 HV after 1 h at 400 C | 300 - 1000 h salt spray depending on thickness and phosphorus | Conductive, contact resistance higher than bare metal | Bright to matte silver, can be blackened | 100 percent build: 1 um up is 1 um per side, so mask or compensate | 400 | 耐磨 耐腐蚀防护 导电接地 耐高温 | ASTM B733, ISO 4527, GB/T 13913 | Hydraulic spools, actuator parts, complex internal bores, valve components, wear faces ground after coating |
| Hard chrome plating镀硬铬 | Plating, electrolytic | Steel, copper, aluminium with an undercoat | 20 - 100 um | 800 - 1100 HV; the classic wear and build-up layer | Limited alone because of microcracks, 200 - 500 h with a nickel undercoat | Conductive | Bright blue silver, satin when ground | 100 percent build, then ground back to size | 400 | 耐磨 低摩擦脱模 | ISO 6158, GB/T 11379 | Hydraulic rods, mould cores, press tools, wear rings, salvage of worn shafts |
| Nickel plating, electrolytic电镀镍 | Plating, electrolytic | Steel, copper, brass, zinc | 5 - 40 um | 200 - 400 HV, moderate | Barrier and decorative, 100 - 300 h | Conductive | Bright silver, takes a high polish | 100 percent build | 300 | 耐腐蚀防护 外观装饰 导电接地 | ASTM B689, ISO 1456 as a system | Barrier layer under gold, electronics hardware, decorative trim, solderable surfaces |
| Zinc plating, trivalent镀锌（三价钝化） | Plating, electrolytic | Steel | 5 - 25 um | 55 - 150 HV, cosmetic only | 96 h clear to 500 h yellow, lead free trivalent systems | Conductive, sacrificial to steel | Blue white, yellow, black | 100 percent build, thin enough to ignore on most features | 120 | 耐腐蚀防护 导电接地 | ISO 2081, ASTM B633, GB/T 9799 | Fasteners, brackets, welded and sheet metal frames, general hardware |
| Zinc nickel plating锌镍合金电镀 | Plating, electrolytic | Steel | 8 - 15 um | 200 - 280 HV | 720 - 1500 h salt spray, strongest of the zinc family | Conductive, sacrificial | Grey silver, black available | 100 percent build, mask fine pitch threads | 180 | 耐腐蚀防护 导电接地 | ISO 19598, ASTM B841, GB/T 5267.2 | Automotive fasteners, brake and under-hood hardware, high corrosion chassis parts |
| Zinc flake coating锌铝涂层（达克罗） | Dip and cure coating | Steel | 4 - 10 um | No hardening; works on class 12.9 without hydrogen embrittlement | 500 - 1000 h salt spray | Conductive, sacrificial | Silver grey or black, matte | 100 percent build but very thin, threads usually stay usable | 300 | 耐腐蚀防护 耐高温 | ISO 10683, GB/T 18684 | High strength fasteners, springs, chassis hardware, parts that cannot be baked after plating |
| Passivation, citric or nitric钝化 | Conversion coating | Stainless steel | Removes free iron, no layer added | No hardness change; it restores the passive film instead of adding a coating | Improves the alloy's own resistance by removing the contamination that starts pitting | Conductive, contact resistance unchanged | Unchanged to slightly brighter | No measurable size change, which is why it is safe on tight tolerances | 600 | 耐腐蚀防护 食品医药卫生 医疗器械 耐化学品 | ASTM A967, AMS 2700, GB/T 25150 | Every machined 300-series part bound for medical, food, pharma or chemical service |
| Electropolishing电解抛光 | Electrochemical removal | Stainless steel, some copper and aluminium | 5 - 25 um removed | No hardening; removes the damaged layer and deburrs in the same step | Improves: craters and inclusions go and chromium enriches at the surface | Conductive | Bright, mirror like, edges rounded | Removes 5 to 25 um per side, so finish before the final size or size the stock up | 600 | 食品医药卫生 医疗器械 耐化学品 低摩擦脱模 外观装饰 | ASTM B912, ISO 15730 | Hygienic pharma and food parts, medical instruments, semiconductor gas path components, fine deburring |
| Chromate conversion coating铬化处理（三价） | Conversion coating | Aluminum | 0.05 - 3 um | No hardening | Moderate alone, excellent as a paint base, 168 - 336 h | Keeps metal to metal contact: low contact resistance, which is why it is used for grounding and EMI | Clear to light yellow or blue | Effectively no size change | 120 | 导电接地 耐腐蚀防护 | MIL-DTL-5541, ISO 10546, GB/T 8013.2 | Chassis and enclosure grounding points, RF and EMI joints, paint and bond preparation |
| Black oxide发黑（黑氧化） | Conversion coating | Steel, stainless and copper variants | 0.5 - 2 um | No hardening | Minimal alone, 24 - 96 h, needs oil or wax to hold | Conductive | Matte black to deep black | About 1 um, negligible on most features | 200 | 外观装饰 耐腐蚀防护 耐磨 | MIL-DTL-13924, GB/T 15519 | Tooling, instrument components, low glare optical housings, parts that must look black |
| Phosphate coating磷化 | Conversion coating | Steel | 2 - 15 um | Porous crystalline layer, no hardening; manganese phosphate helps break-in | 24 - 100 h with oil, excellent paint and oil adhesion | Not used for grounding | Matte grey to dark grey | Small build, texture rather than thickness | 200 | 耐腐蚀防护 低摩擦脱模 外观装饰 | ISO 9717, GB/T 11376 | Gears and camshafts that must retain oil, base for paint, non reflective machine parts |
| Powder coating粉末喷涂 | Organic coating | Steel, aluminium | 60 - 120 um | Soft relative to metal; it protects, it does not carry load | 500 - 1000 h salt spray with proper pretreatment | Insulating | Any colour and gloss level, smooth or textured | The thickness dominates the tolerance: +60 to +120 um per side, mask threads and bores | 120 | 耐腐蚀防护 电绝缘 外观装饰 食品医药卫生 | Qualicoat and GSB systems, ISO 12944 system | Outdoor enclosures, frames, machine covers, consumer equipment; check the 180 to 200 C cure against aluminium temper |
| Liquid paint喷漆 | Organic coating | Steel, aluminium, plastics | 20 - 60 um | Soft | System dependent, 100 - 500 h | Insulating | Any colour, gloss or matte | Thinner than powder but still visible on a tolerance: +20 to +60 um per side | 120 | 耐腐蚀防护 外观装饰 电绝缘 | ISO 12944, SSPC systems | Large frames, welded assemblies, colour matching to a customer palette, touch-up |
| PTFE coating特氟龙涂层 | Dry film lubricant | Steel, aluminium, stainless with a primer | 15 - 40 um | Soft, friction coefficient 0.05 - 0.15, no load carrying hardness | Good chemical barrier | Insulating | Opaque white, dark green, grey or black by system | Build 15 to 40 um per side, mask sealing faces unless coating there is intended | 260 | 低摩擦脱模 耐化学品 食品医药卫生 | AMS 2515, coating supplier system specification | Mould release, pump and valve internals, food contact surfaces, low friction slides and seals |
| PVD coating, TiN TiAlN CrN DLC物理气相沉积 | Vapour deposition | Steel, stainless, carbide, titanium | 1 - 5 um | TiN 2000 - 2400 HV, TiAlN 3000 - 3400 HV, CrN 1600 - 2000 HV, DLC 2000 - 4000 HV with low friction | Depends on density: a porous coating on steel can accelerate galvanic attack, so pair it with passivation or nickel | TiN and CrN conductive, DLC semi insulating or insulating | TiN gold, TiAlN violet to black, CrN silver grey, DLC black | 1 to 5 um only, so a precision part stays a precision part | 600 | 耐磨 低摩擦脱模 外观装饰 耐高温 医疗器械 | ISO 14577 and EN 1071 test methods, coating supplier specification | Cutting tools, forming dies, mould surfaces, medical instruments, black wear parts that must stay dimensionally exact |
| CVD coating化学气相沉积 | Vapour deposition | Steel, carbide, ceramic | 5 - 20 um | 3000 - 4000 HV with excellent adhesion | Very good, dense layer | Conductive | Grey to black, matte | 5 to 20 um per side | 900 | 耐磨 耐高温 | ISO 14577, supplier specification | Indexable inserts, extrusion dies, nozzles; the 900 to 1000 C process means steel parts need a post-coating heat treatment |
| Bead blasting喷砂 | Mechanical surface | All metals, plastics with soft media | Removes 1 - 10 um | No hardening; shot peening is the process for that | Neutral: improves paint adhesion, but embedded fines hurt corrosion if not cleaned | Conductive | Uniform matte, satin, hides machining marks | Small removal, but sharp edges round and thin sections can move | n/a | 外观装饰 低摩擦脱模 前处理去毛刺 | ISO 8503 for the profile, SAE J444 for media | Satin finish before anodizing, weld and heat scale removal, mould cleaning, uniform appearance before coating |
| Shot peening喷丸强化 | Mechanical surface | Steel, aluminium, titanium | No material removed | Cold works the surface layer and raises fatigue life, two to ten times on a properly specified part | Neutral to slightly positive | Conductive | Matte, dimpled under a low angle light | Controlled by Almen intensity, not microns; it can move flatness, so peen before final grinding | n/a | 疲劳寿命 | SAE J442 and J443, AMS 2430 | Connecting rods, springs, gear roots, fillets that crack, landing gear and turbine hardware |
| Mechanical polishing机械抛光 | Mechanical surface | All metals | Removes to reach the target Ra | No hardening | Improves: coarse pits hold corrodents | Conductive | Satin to mirror | Removes enough to matter on a tight diameter, so polish before the final size | n/a | 外观装饰 低摩擦脱模 食品医药卫生 医疗器械 | ISO 21920 for the parameter, shop method | Optical surfaces, mould cavities, sealing faces, medical and food contact surfaces |
| Laser marking and engraving激光打标与雕刻 | Beam process | All metals, most plastics | 0.01 - 0.5 um marking | No change to the bulk material | Neutral; on stainless a light mark can slightly reduce local corrosion resistance | Conductive | Dark oxide mark, frosted, or colour on stainless | No measurable dimensional effect for marking, deep engraving removes real material | n/a | 标识追溯 外观装饰 | UDI per 21 CFR 830 for medical devices, customer marking specification | UDI and serial numbers, 2D Data Matrix codes, logos, scale marks, tool numbers |
| Nitriding, gas or plasma气体渗氮 / 离子渗氮 | Thermochemical diffusion | Alloy steels such as 42CrMo and 38CrMoAl, some stainless and titanium | Case 100 - 600 um deep | 900 - 1200 HV surface with a tough core: a diffusion layer, so it cannot chip off | Mild improvement | Conductive, surface resistance rises slightly | Grey to silver, with a visible size change on precision work | Growth of roughly 10 to 30 um on the surface, so grind datums and bores after treatment | 550 | 耐磨 表面硬化 耐高温 疲劳寿命 耐腐蚀防护 | GB/T 18177, AMS 2759 series | Gear and spline flanks, mould and die surfaces, pump and valve internals, wear critical shafts. Low distortion because there is no quench |
| Carburizing and hardening渗碳淬火 | Thermochemical diffusion | Low carbon steels such as 20CrMnTi and 8620 | Case 300 - 2000 um deep | 58 - 62 HRC case with a tough core; the classic gear treatment | Poor alone, needs plating or paint | Conductive | Grey to dark grey after tempering | Quench distortion is real, so leave grinding stock on datums | 200 | 耐磨 表面硬化 疲劳寿命 | GB/T 9450, ISO 2639 for case depth | Gears, pinions, cams, splines, bearing races, parts needing a hard skin and a shock resistant core |
| Induction hardening感应淬火 | Local heat treatment | Medium carbon and alloy steels such as 1045 and 4140 | Case 1000 - 5000 um deep | 55 - 62 HRC in the treated band only | Poor in the treated zone without protection | Conductive | Dark martensitic grey | Distortion limited to the quenched zone, finish grind after treatment | 250 | 耐磨 表面硬化 疲劳寿命 | GB/T 5617 | Shaft journals, splines, gear teeth, bearing seats, the local wear band on a large part |
| Nitrocarburizing, salt bath or gas氮碳共渗（QPQ 类） | Thermochemical diffusion | Steel, stainless | Compound zone 10 - 30 um plus diffusion | 600 - 800 HV with an oxidised black outer layer that also cuts friction | 200 - 500 h with the oxidation step, very good for a black finish | Conductive | Uniform matte black | Same order of growth as nitriding: allow 10 to 30 um | 400 | 耐磨 耐腐蚀防护 外观装饰 低摩擦脱模 | No single ISO number: specify compound zone and diffusion depth on the drawing | Black wear parts, hydraulic components, fasteners, parts that need wear plus black appearance in one step |
| Titanium anodizing钛阳极氧化 | Anodizing | Titanium and titanium alloys | 0.02 - 1 um | Thin oxide that greatly reduces galling and fretting | Titanium is already passive: this is for function and identification, not extra corrosion | Effectively conductive at low voltage, very thin dielectric layer | Interference colours by voltage: bronze, purple, blue, gold, green | Under 0.2 um, so precision is preserved | 300 | 医疗器械 外观装饰 低摩擦脱模 耐腐蚀防护 | ASTM F86, AMS 2488 | Surgical instruments, implant identification marking, titanium fasteners, parts that must not gall |
図面を描く段階で気づける警告: 陽極酸化やめっきをかける狭い穴（補正かマスキングが必要）、粉体塗装部品への平面度 0.005 mm の指定 （膜厚が公差より厚い）、陽極酸化した筐体のアースねじ、疲労に耐える必要のある硬質陽極酸化の隅肉、そして粗い面への PVD （膜が砥粒の起伏に沿ってしまう）。
表面性状: Ra と Rz
値の系列は GB/T 1031-2009（ISO 4287）に基づきます。Ra が標準のパラメータで、Ra では足りない非常に細かい面や粗い面では、 山と谷の高さを表す Rz が効きます。細かい側は機能が求める場合だけ選んでください。Ra を詰めると加工時間が増え、潤滑剤の保持性が悪くなることがあります。
Ra 系列 (um)
0.012 0.025 0.05 0.1 0.2 0.4 0.8 1.6 3.2 6.3 12.5 25 50 100
Rz 系列 (um)
0.025 0.05 0.1 0.2 0.4 0.8 1.6 3.2 6.3 12.5 25 50 100 200 400 800 1600
測定長
| Ra 範囲 (um) | カットオフ波長 lr (mm) | 測定長 ln (mm) |
|---|---|---|
| >=0.008 to 0.02 | 0.08 | 0.4 |
| >0.02 to 0.1 | 0.25 | 1.25 |
| >0.1 to 2.0 | 0.8 | 4 |
| >2.0 to 10.0 | 2.5 | 12.5 |
| >10.0 to 80.0 | 8 | 40 |
Ra の適用範囲
| Ra (um) | 代表的な用途（GB/T 1031 抜粋） |
|---|---|
| 0.8 | Fits needing guaranteed concentricity: P6 and P5 rolling bearing seats, spigot bores IT7, plain pins IT8 |
| 0.2 | Long life mating surfaces: IT6 and IT5 bores and shafts, gear teeth 6th grade, journal bearings P5 |
| 0.1 | Heavily loaded, variable stress surfaces: hydraulic cylinder bores and rods, gland grooves |
| 0.05 | Spindle bearings P4 and above, friction faces of clutches, precision gauge measuring faces |
| 0.025 | Precision gauge balls and rolls, high pressure pump plunger pairs, gauge blocks over 100 mm |
目安として、旋削面やフライス面では Rz は Ra のおよそ 4 倍から 7 倍です。合否判定のために換算しないでください。 測定するのは図面が指定したパラメータです。
各加工法が保てる水準
表面性状の指定と工程が噛み合っているかを確認できます。フライス加工のポケットに Ra 0.2 が指定されていれば、 工程は研削、ラッピング、研磨に切り替わる必要があり、価格もそれに伴って変わります。
| 加工法 | 到達できる Ra (um) |
|---|---|
| Rough milling | Ra 3.2 - 12.5 um |
| Finish milling | Ra 0.8 - 1.6 um |
| Fine milling, high speed small stepover | Ra 0.4 - 0.8 um |
| Rough turning | Ra 3.2 - 6.3 um |
| Finish turning | Ra 0.8 - 1.6 um |
| Fine turning with wiper insert | Ra 0.4 - 0.8 um |
| Drilling | Ra 3.2 - 12.5 um |
| Reaming | Ra 0.8 - 1.6 um |
| Fine boring | Ra 0.4 - 0.8 um |
| Broaching | Ra 0.4 - 1.6 um |
| Surface grinding | Ra 0.1 - 0.8 um |
| Cylindrical grinding | Ra 0.1 - 0.4 um |
| Honing | Ra 0.05 - 0.4 um |
| Lapping | Ra 0.012 - 0.1 um |
| Wire EDM, multi pass | Ra 0.2 - 1.6 um |
| Die sinking EDM | Ra 0.4 - 3.2 um |
| Bead blasting | Ra 1.6 - 6.3 um |
| Shot peening | Ra 1.6 - 6.3 um |
| Mechanical polishing | Ra 0.012 - 0.1 um |
| Electropolishing | Ra 0.05 - 0.4 um |
| 判断の目安 | 実務への影響 |
|---|---|
| Ra 3.2 またはそれより粗い | 加工のまま。追加工程も割増もありません。 |
| Ra 1.6 | 通常の仕上げ加工。多くの嵌合面とシール面の標準です。 |
| Ra 0.8 | 切れ刃を鋭くし、剛性の高い取り付けで行う精密仕上げ。検査の手間は増えますが、費用はほとんど変わりません。 |
| Ra 0.4 またはそれより細かい | 追加工程が必要です。研削、ホーニング、ラッピング、研磨のいずれか。ここで価格が跳ねます。 |
| Ra 0.1 またはそれより細かい | 特殊領域です。条件と測定方法を指定し、専用の工程を組む前提で進めてください。 |
表面性状は熱処理や被覆と綱引きになります。窒化は研削面を粗くし、硬質陽極酸化は加工痕に沿い、 ブラストはおよそ Ra 1.6 の下限を作るため、その後の研磨で削り取る必要があります。
KGL は表面をどう決めて検査するか
| 当社の対応 | 価格に効く理由 |
|---|---|
| 表面性状を数値と測定方法で図面に指定 | Ra 0.8 に測定方法を添えて指定するため、検査と製造が同じ合否基準で動けます |
| 公差と膜厚をまとめて見積もり前に確認 | 膜厚が公差を超える場合は、処理の後ではなく見積もりの時点でお伝えします |
| 陽極酸化と塗装は同一注文を同じロットで処理 | 同じ合金、同じ浴、同じロットで処理すると、納品全体で色と膜厚がそろいます |
| 基準面の最終研削は処理の後に行う | 窒化や焼入れした部品は処理後に研削し、基準の幾何が正しい状態で仕上がります |
| 表面検査は CMM と粗さ測定を組み合わせる | 輪郭、Ra、膜厚を同じ検査票に記載します。図面が求めるところで報告します |
| よくいただく質問 | 短い回答 |
|---|---|
| 陽極酸化しても穴寸法を保てますか | 補正するかマスキングすれば可能です。寸法を変えたくない面をご指定ください。マスキングの手間も見積もりに含めます。 |
| 黒色の陽極酸化が茶色になったのはなぜですか | 合金組成、染色浴、膜厚で色味が動きます。ロット単位の処理と色見本の保管で再現性が戻ります。 |
| アースを取る筐体にはクロメートと陽極酸化のどちらですか | 金属接触を保つクロメートです。陽極酸化は耐摩耗と色に優れますが絶縁します。 |
| アルミニウムで最も耐摩耗な表面は何ですか | 硬質陽極酸化、寸法を変えたくない場合は PVD です。鋼では窒化の方がはるかに高い負荷に耐えます。 |
図面の表面処理と公差が矛盾していませんか？
2D と 3D のデータをお送りください。24時間以内にお見積もりを回答し、膜厚、公差、材料が噛み合わない箇所を、材料を切る前に指摘します。MOQ はなく、1 個から対応します。