{"id":2965,"date":"2026-07-26T00:40:33","date_gmt":"2026-07-25T16:40:33","guid":{"rendered":"https:\/\/bravofabs.com\/stainless-steel-fabrication-guide\/"},"modified":"2026-07-26T00:47:28","modified_gmt":"2026-07-25T16:47:28","slug":"stainless-steel-fabrication-guide","status":"publish","type":"post","link":"https:\/\/bravofabs.com\/stainless-steel-fabrication-guide\/","title":{"rendered":"Stainless Steel Fabrication Guide: Grades, Welding &amp; Surface Finishes"},"content":{"rendered":"\n<h2 class=\"wp-block-heading\">Key Takeaways<\/h2>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>304 stainless steel is the workhorse grade<\/strong> for roughly 70% of stainless fabrication projects \u2014 it balances corrosion resistance, weldability, and cost better than any other grade.<\/li>\n<li><strong>316 adds 2\u20133% molybdenum<\/strong> for chloride and chemical resistance, making it the standard for marine, pharmaceutical, and food-processing applications \u2014 at roughly 1.4\u20131.75\u00d7 the material cost of 304.<\/li>\n<li><strong>410 and 17-4PH are hardenable martensitic grades<\/strong> \u2014 410 is the budget hardenable option (0.6\u20130.8\u00d7 304 cost), while 17-4PH reaches aerospace-level strength (up to 1,450 MPa yield) via heat treatment.<\/li>\n<li><strong>Stainless machines 2\u20134\u00d7 slower than aluminum<\/strong> and consumes 3\u201310\u00d7 more tooling \u2014 machining time, not raw material cost, drives 70\u201380% of the final part price.<\/li>\n<li><strong>Passivation (ASTM A967) is not optional.<\/strong> Every machined or welded stainless part needs passivation to remove free iron and restore the protective chromium oxide layer \u2014 skipping it leads to rust on &#8220;stainless&#8221; parts within weeks.<\/li>\n<li><strong>TIG welding is the gold standard for stainless<\/strong> \u2014 highest precision, best cosmetic finish, and full control over heat input. MIG is faster for thick sections; laser welding is 4\u00d7 faster than TIG but requires high capital investment.<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Stainless steel<\/strong> is everywhere in modern manufacturing \u2014 from surgical instruments and food-processing equipment to marine hardware and chemical plant components. Its chromium content (minimum 10.5%) forms a self-healing oxide layer that resists rust, acids, and high temperatures in ways that carbon steel and aluminum cannot match. But &#8220;stainless steel&#8221; is a family of dozens of alloys, and choosing the wrong one \u2014 or skipping a critical post-processing step \u2014 can turn a premium material into a warranty claim.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">This guide compares the four stainless grades most commonly encountered in CNC machining and sheet metal fabrication \u2014 <strong>304, 316, 410, and 17-4PH<\/strong> \u2014 and covers welding methods, surface finishes, tolerance expectations, and the real cost drivers that determine your quote.<\/p>\n\n\n\n<figure class=\"wp-block-table\"><table style=\"width:100%;border-collapse:collapse\"><thead><tr style=\"background:#004c97;color:#fff\"><th>Grade<\/th><th>Type<\/th><th>Best For<\/th><th>Tensile \/ Yield (MPa)<\/th><th>Relative Cost<\/th><\/tr><\/thead><tbody><tr><td><strong>304<\/strong><\/td><td>Austenitic<\/td><td>General fabrication, enclosures, kitchen equipment<\/td><td>520\u2013720 \/ 215<\/td><td>$ (baseline)<\/td><\/tr><tr style=\"background:#f4f7fb\"><td><strong>316<\/strong><\/td><td>Austenitic<\/td><td>Marine, chemical, pharmaceutical<\/td><td>530\u2013680 \/ 290<\/td><td>$$ (1.4\u20131.75\u00d7)<\/td><\/tr><tr><td><strong>410<\/strong><\/td><td>Martensitic<\/td><td>Wear parts, cutlery, valve components<\/td><td>517 \/ 310 (annealed)<\/td><td>$ (0.6\u20130.8\u00d7)<\/td><\/tr><tr style=\"background:#f4f7fb\"><td><strong>17-4PH<\/strong><\/td><td>Precipitation-hardening<\/td><td>Aerospace, high-strength shafts, nuclear<\/td><td>1,000\u20131,450 \/ 1,000\u20131,310*<\/td><td>$$$ (2\u20133\u00d7)<\/td><\/tr><\/tbody><\/table><figcaption class=\"wp-element-caption\">Quick grade selector \u2014 *17-4PH strength varies by heat treatment condition (H1150 \u2192 H900). Values from AK Steel and MatWeb datasheets.<\/figcaption><\/figure>\n\n\n\n<h2 class=\"wp-block-heading\">Stainless Steel Grades Compared: 304, 316, 410 &amp; 17-4PH<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Stainless steels fall into five families \u2014 austenitic, ferritic, martensitic, duplex, and precipitation-hardening \u2014 but for machined and fabricated parts, four grades dominate. Here is what each one actually delivers on the shop floor.<\/p>\n\n\n\n<figure class=\"wp-block-table\"><table style=\"width:100%;border-collapse:collapse\"><thead><tr style=\"background:#004c97;color:#fff\"><th>Property<\/th><th>304<\/th><th>316<\/th><th>410<\/th><th>17-4PH (H900)<\/th><\/tr><\/thead><tbody><tr><td><strong>Tensile strength (MPa)<\/strong><\/td><td>520\u2013720<\/td><td>530\u2013680<\/td><td>517<\/td><td>1,310\u20131,450<\/td><\/tr><tr style=\"background:#f4f7fb\"><td><strong>Yield strength (MPa)<\/strong><\/td><td>215<\/td><td>290<\/td><td>310<\/td><td>1,000\u20131,310<\/td><\/tr><tr><td><strong>Hardness<\/strong><\/td><td>70 HRB<\/td><td>79 HRB<\/td><td>80 HRB<\/td><td>33\u201345 HRC<\/td><\/tr><tr style=\"background:#f4f7fb\"><td><strong>Machinability (vs 1112)<\/strong><\/td><td>~45%<\/td><td>~36%<\/td><td>~54%<\/td><td>~45\u201350%<\/td><\/tr><tr><td><strong>Weldability<\/strong><\/td><td>Excellent<\/td><td>Good (slightly more sensitive)<\/td><td>Poor \u2014 requires preheat + PWHT<\/td><td>Good \u2014 but loses strength in HAZ<\/td><\/tr><tr style=\"background:#f4f7fb\"><td><strong>Corrosion resistance<\/strong><\/td><td>Good \u2014 general purpose<\/td><td>Excellent \u2014 chloride\/pitting resistant<\/td><td>Fair \u2014 lowest of the four<\/td><td>Good \u2014 comparable to 304<\/td><\/tr><tr><td><strong>Magnetic?<\/strong><\/td><td>No*<\/td><td>No*<\/td><td>Yes<\/td><td>Yes<\/td><\/tr><tr style=\"background:#f4f7fb\"><td><strong>Hardenable by heat treat?<\/strong><\/td><td>No<\/td><td>No<\/td><td>Yes<\/td><td>Yes (precipitation hardening)<\/td><\/tr><tr><td><strong>Relative material cost<\/strong><\/td><td>1.0\u00d7 (baseline)<\/td><td>1.4\u20131.75\u00d7<\/td><td>0.6\u20130.8\u00d7<\/td><td>2\u20133\u00d7<\/td><\/tr><\/tbody><\/table><figcaption class=\"wp-element-caption\">Full grade comparison. *304\/316 may become slightly magnetic after cold working. Sources: AK Steel, Atlas Steels, MatWeb, Geospace.<\/figcaption><\/figure>\n\n\n\n<h3 class=\"wp-block-heading\">304 \u2014 The All-Purpose Workhorse<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>304<\/strong> (UNS S30400, EN 1.4301) is the most commonly specified stainless steel worldwide. An austenitic chromium-nickel alloy with 18\u201320% Cr and 8\u201310.5% Ni, it delivers excellent corrosion resistance in most environments, welds cleanly with all common processes, and cannot be hardened by heat treatment \u2014 only by cold working. At 215 MPa yield strength, it covers general fabrication, food-processing equipment, architectural panels, and kitchen components. For <a href=\"https:\/\/bravofabs.com\/sheet-metal-fabrication-services\/\">sheet metal fabrication<\/a>, 304 is the default stainless choice for bent enclosures, brackets, and panels.<\/p>\n\n\n\n<p class=\"has-background wp-block-paragraph\" style=\"background-color:#f8f9fb;padding-top:10px;padding-right:14px;padding-bottom:10px;padding-left:14px\"><strong>Best for:<\/strong> general fabrication, enclosures, kitchen equipment, architectural panels, indoor structural components.<br><strong>Avoid when:<\/strong> chloride exposure (seawater, swimming pools, chemical processing) \u2014 upgrade to 316.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">316 \u2014 Chloride and Chemical Resistance<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>316<\/strong> (UNS S31600, EN 1.4401) takes the 304 formula and adds 2\u20133% molybdenum \u2014 and that single element makes all the difference. Molybdenum dramatically improves resistance to pitting corrosion from chlorides (salt water, de-icing salts, bleach) and acidic environments. This is why 316 is the mandatory grade for marine hardware, pharmaceutical processing equipment, and chemical plant components. Yield strength is slightly higher than 304 at 290 MPa. The trade-off: machinability drops to ~36% (vs 304&#8217;s ~45%) because 316 work-hardens more aggressively during cutting, and material cost runs 1.4\u20131.75\u00d7 304.<\/p>\n\n\n\n<p class=\"has-background wp-block-paragraph\" style=\"background-color:#f8f9fb;padding-top:10px;padding-right:14px;padding-bottom:10px;padding-left:14px\"><strong>Best for:<\/strong> marine environments, chemical processing, pharmaceutical, surgical instruments, outdoor coastal applications.<br><strong>Avoid when:<\/strong> indoor general-purpose fabrication \u2014 304 does the same job for 30\u201340% less material cost.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">410 \u2014 The Budget Hardenable Grade<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>410<\/strong> (UNS S41000, EN 1.4006) is a martensitic stainless steel with 11.5\u201313.5% chromium and minimal nickel. It is the only grade in this group that can be hardened by conventional quench-and-temper heat treatment, reaching moderate strength levels while being the cheapest stainless option at 0.6\u20130.8\u00d7 the cost of 304. The catch: corrosion resistance is the lowest of the four \u2014 bare 410 will rust in humid or mildly corrosive environments where 304 would be fine. It also has poor weldability and typically requires preheat (200\u2013300\u00b0C) and post-weld heat treatment to avoid cracking.<\/p>\n\n\n\n<p class=\"has-background wp-block-paragraph\" style=\"background-color:#f8f9fb;padding-top:10px;padding-right:14px;padding-bottom:10px;padding-left:14px\"><strong>Best for:<\/strong> wear parts, valve stems, pump shafts, cutlery, steam turbine blades, applications needing moderate hardness on a budget.<br><strong>Avoid when:<\/strong> any corrosion exposure, welding required, or cosmetic appearance matters \u2014 410 will tarnish.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">17-4PH \u2014 Aerospace-Grade Strength<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>17-4PH<\/strong> (UNS S17400, EN 1.4542) is a precipitation-hardening martensitic stainless steel that achieves extraordinary strength through a simple aging heat treatment rather than conventional quench-and-temper. Depending on the aging temperature (H1150 at 620\u00b0C down to H900 at 482\u00b0C), yield strength ranges from 1,000 MPa to over 1,310 MPa \u2014 placing it in the same league as alloy steels while retaining corrosion resistance comparable to 304. It machines well (45\u201350% machinability in the solution-annealed Condition A), welds acceptably (though the HAZ loses strength), and is the material of choice for aerospace structural components, high-strength shafts, nuclear reactor parts, and military hardware. The cost premium is significant at 2\u20133\u00d7 304.<\/p>\n\n\n\n<p class=\"has-background wp-block-paragraph\" style=\"background-color:#f8f9fb;padding-top:10px;padding-right:14px;padding-bottom:10px;padding-left:14px\"><strong>Best for:<\/strong> aerospace fittings, high-strength shafts, nuclear components, military hardware, gears requiring both strength and corrosion resistance.<br><strong>Avoid when:<\/strong> 304 or 316 meets the load case \u2014 do not pay 2\u20133\u00d7 for strength the part does not need. Also avoid if the part must be welded in the final heat-treated condition.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Welding Stainless Steel: TIG, MIG, and Laser Compared<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Stainless steel welding is fundamentally different from carbon steel welding. The chromium that gives stainless its corrosion resistance forms chromium carbides in the heat-affected zone if cooling is too slow \u2014 a phenomenon called <strong>sensitization<\/strong> that destroys local corrosion resistance. Every stainless welding process must control heat input, use the correct filler metal, and (for full-penetration welds) purge the back side of the joint with inert gas to prevent oxidation \u2014 known as <strong>&#8220;sugaring&#8221;<\/strong> \u2014 which appears as a black, crusty oxide on the weld root.<\/p>\n\n\n\n<figure class=\"wp-block-table\"><table style=\"width:100%;border-collapse:collapse\"><thead><tr style=\"background:#004c97;color:#fff\"><th>Process<\/th><th>Speed<\/th><th>Precision<\/th><th>Heat Distortion<\/th><th>Cost<\/th><th>Best For<\/th><\/tr><\/thead><tbody><tr><td><strong>TIG (GTAW)<\/strong><\/td><td>Slow<\/td><td>Highest<\/td><td>Low<\/td><td>$$ (skilled labor)<\/td><td>Thin sheet metal, cosmetic welds, food\/pharma piping, precision fabrications<\/td><\/tr><tr style=\"background:#f4f7fb\"><td><strong>MIG (GMAW)<\/strong><\/td><td>2\u20133\u00d7 TIG<\/td><td>Medium<\/td><td>Medium<\/td><td>$<\/td><td>Thick sections (&gt;3 mm), structural welds, high-volume production<\/td><\/tr><tr><td><strong>Laser Welding<\/strong><\/td><td>4\u00d7 TIG<\/td><td>Very High<\/td><td>Minimal<\/td><td>$$$ (equipment)<\/td><td>Thin sheet (&lt;3 mm), minimal distortion required, high-volume automation<\/td><\/tr><\/tbody><\/table><figcaption class=\"wp-element-caption\">Welding process comparison for stainless steel. All processes require correct filler metal matching and back-purging for full-penetration welds.<\/figcaption><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Filler metal selection matters.<\/strong> For 304 base metal, use 308L filler (the &#8220;L&#8221; designates low carbon to prevent sensitization). For 316, use 316L filler. Using a 308L rod on 316 will leave the weld zone without molybdenum protection \u2014 it will pit long before the surrounding base metal. 410 requires a 410 filler or 309L for dissimilar joints, and always needs preheat and post-weld heat treatment. 17-4PH uses 17-4PH filler or 630 matching composition.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Passivation, Electropolishing, and Surface Finishes<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">The single most common post-processing mistake with stainless steel parts is <strong>skipping passivation<\/strong>. Machining, grinding, and welding all embed microscopic particles of free iron into the stainless surface from tooling, fixtures, and shop dust. Those iron particles rust \u2014 and because they sit on stainless, the rust appears to come from the stainless itself. Passivation (ASTM A967) uses nitric or citric acid to dissolve surface iron and allow the natural chromium oxide layer to reform uniformly. It does not change surface roughness (Ra) or dimensional tolerances \u2014 it is purely a corrosion-protection step.<\/p>\n\n\n\n<figure class=\"wp-block-table\"><table style=\"width:100%;border-collapse:collapse\"><thead><tr style=\"background:#004c97;color:#fff\"><th>Finish Process<\/th><th>Standard<\/th><th>Typical Ra Achieved<\/th><th>Purpose<\/th><\/tr><\/thead><tbody><tr><td><strong>Passivation<\/strong><\/td><td>ASTM A967<\/td><td>Unchanged from base<\/td><td>Remove free iron, restore Cr\u2082O\u2083 layer \u2014 corrosion protection only<\/td><\/tr><tr style=\"background:#f4f7fb\"><td><strong>Electropolishing<\/strong><\/td><td>ASTM B912<\/td><td>Improves Ra 10\u201340%<\/td><td>Simultaneously passivates AND smooths surface; removes burrs, micro-cracks<\/td><\/tr><tr><td><strong>Bead blasting<\/strong><\/td><td>\u2014<\/td><td>Ra 1.0\u20133.5 \u03bcm<\/td><td>Uniform matte texture; hides tool marks; prep before passivation<\/td><\/tr><tr style=\"background:#f4f7fb\"><td><strong>Pickling<\/strong><\/td><td>ASTM A380<\/td><td>Unchanged<\/td><td>Removes weld heat tint (oxide scale); more aggressive than passivation<\/td><\/tr><tr><td><strong>As-machined + passivation<\/strong><\/td><td>ASTM A967<\/td><td>Ra 3.2 \u03bcm (default)<\/td><td>Functional industrial finish \u2014 minimum acceptable for stainless<\/td><\/tr><\/tbody><\/table><figcaption class=\"wp-element-caption\">Surface finish options for stainless parts. Electropolishing is the only process that simultaneously improves surface finish AND passivates.<\/figcaption><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Callout tip:<\/strong> if your drawing says &#8220;304 stainless&#8221; without mentioning passivation, ask your supplier whether passivation is included. Many shops default to &#8220;as-machined&#8221; and ship without it \u2014 and the part will arrive looking fine but develop rust spots within weeks. Always specify <strong>&#8220;Passivate per ASTM A967&#8221;<\/strong> on the drawing or purchase order.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Tolerances for CNC Machined and Sheet Metal Stainless Parts<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Stainless holds tolerances differently depending on whether you are machining from solid stock or forming from sheet. Its higher strength and tendency to work-harden give it both advantages and disadvantages relative to aluminum.<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>CNC machining (milled from billet):<\/strong> Standard tolerance is \u00b10.005 in (\u00b10.13 mm). Precision down to \u00b10.001 in (\u00b10.025 mm) is achievable on 304 and 316, but the part may require stress-relief between roughing and finishing to prevent movement. 17-4PH in Condition A machines cleanly to tight tolerances but will move slightly during subsequent aging heat treatment \u2014 always machine H1150 or H900 condition features after aging where possible.<\/li>\n<li><strong>Sheet metal fabrication:<\/strong> Cut features (laser\/punch): \u00b10.005\u20130.015 in (\u00b10.13\u20130.38 mm). Formed dimensions: \u00b10.010\u20130.030 in (\u00b10.25\u20130.76 mm). Stainless has less springback than aluminum during bending, so formed tolerances are actually tighter on stainless than on aluminum for the same bend geometry.<\/li>\n<li><strong>Welded assemblies:<\/strong> Expect \u00b10.030\u20130.060 in (\u00b10.76\u20131.5 mm) for welded dimensions due to thermal distortion. Post-weld machining or straightening may be required for tighter assemblies \u2014 factor this into lead time and cost.<\/li>\n<\/ul>\n\n\n\n<h2 class=\"wp-block-heading\">Why Stainless Steel Costs More: The Real Cost Drivers<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Raw material prices explain only part of the stainless premium. Here is where the money actually goes when you order stainless parts:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Raw material: 1.3\u20133\u00d7 aluminum.<\/strong> Stainless steel plate costs roughly $3\u20135\/kg vs aluminum plate at $3\u20136\/kg \u2014 the per-kilo gap is smaller than most buyers assume. The real cost difference emerges in processing.<\/li>\n<li><strong>Machining time: 2\u20134\u00d7 aluminum.<\/strong> Stainless cuts at 60\u2013120 SFM (18\u201337 m\/min) with carbide tooling, compared to 800\u20131,500 SFM for aluminum. A part that takes 15 minutes in aluminum can take 40\u201360 minutes in 304.<\/li>\n<li><strong>Tool wear: 3\u201310\u00d7 more inserts.<\/strong> Stainless work-hardens as it cuts \u2014 the surface ahead of the tool instantly becomes harder than the bulk material. This edge-hardening effect, combined with stainless&#8217;s low thermal conductivity (heat stays in the tool instead of flowing into the chip), accelerates tool wear dramatically.<\/li>\n<li><strong>Net result:<\/strong> A simple bracket that costs $25\u201350 in 6061 aluminum will typically cost $50\u2013120 in 304 stainless \u2014 a 1.5\u20132.5\u00d7 multiplier driven primarily by machining time, not raw material.<\/li>\n<\/ul>\n\n\n\n<h2 class=\"wp-block-heading\">How to Choose the Right Stainless Steel Grade<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Work through these four questions in order \u2014 they eliminate 90% of grade selection mistakes:<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>What is the operating environment?<\/strong> Indoor \/ dry \u2192 304. Coastal \/ marine \/ chemical \u2192 316. Abrasive \/ wear application \u2192 410. Demanding structural load \u2192 17-4PH.<\/li>\n<li><strong>Will it be welded?<\/strong> Yes \u2192 304 or 316 (austenitic grades weld beautifully). 410 requires special procedures. 17-4PH can be welded but loses strength in the HAZ.<\/li>\n<li><strong>What strength do you actually need?<\/strong> Under ~350 MPa yield \u2192 304 or 316. 350\u2013500 MPa \u2192 410 (heat-treated). Above 1,000 MPa \u2192 17-4PH.<\/li>\n<li><strong>Is magnetic response a factor?<\/strong> Non-magnetic required \u2192 304 or 316 (note: may become slightly magnetic after cold working). Magnetic acceptable \u2192 410 or 17-4PH.<\/li>\n<\/ol>\n\n\n\n<h2 class=\"wp-block-heading\">Common Mistakes When Specifying Stainless Steel Parts<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>1. Specifying &#8220;stainless steel&#8221; without a grade number.<\/strong> &#8220;Stainless&#8221; to one supplier means 304; to another it means 409 \u2014 an automotive-grade ferritic stainless with half the corrosion resistance. Always write the full grade: &#8220;304 stainless steel (UNS S30400)&#8221; or &#8220;316L stainless steel (UNS S31603).&#8221; The &#8220;L&#8221; suffix on 304L\/316L designates extra-low carbon (\u22640.03%) for improved weldability \u2014 specify it whenever the part will be welded.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>2. Ordering 316 when 304 would work.<\/strong> 316&#8217;s molybdenum content adds 40\u201375% to material cost. If the part lives indoors, away from chlorides, that premium is wasted. A simple test: will the part ever see salt water, bleach, or acid? If not, 304 is almost certainly sufficient.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>3. Omitting passivation from the purchase order.<\/strong> An as-machined 304 part may look perfect on arrival and develop rust spots within 30 days in a humid warehouse. The free iron embedded during machining rusts \u2014 and because it sits on a stainless surface, it looks like the stainless itself failed. Always specify passivation per ASTM A967. For food, pharmaceutical, or ultra-high-purity applications, specify electropolishing instead \u2014 it passivates and smooths in one step.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>4. Welding 410 without preheat and post-weld heat treatment.<\/strong> 410&#8217;s martensitic structure makes it hardenable by cooling \u2014 and a weld bead cools fast. Without preheat (200\u2013300\u00b0C) and immediate post-weld tempering, the HAZ will contain hard, brittle martensite that cracks under the first load cycle. If the drawing calls for 410 and a weld, budget for heat treatment in both cost and lead time \u2014 or redesign the joint out of the part.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>5. Assuming all stainless is non-magnetic.<\/strong> Only austenitic grades (304, 316) are non-magnetic in the annealed condition \u2014 and even they can become slightly magnetic after cold working (bending, drawing, or heavy machining). Martensitic grades (410) and precipitation-hardening grades (17-4PH) are ferromagnetic. If your application cannot tolerate any magnetic response \u2014 MRI components, sensitive sensors \u2014 verify with a magnet before accepting parts.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Get Your Stainless Parts Made Right<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Stainless steel rewards careful specification and punishes guesswork. Grade selection, welding method, and post-processing steps determine whether your part arrives ready for service or needs rework. BravoFabs machines and fabricates stainless steel parts daily for industrial clients across Europe and North America \u2014 and every RFQ includes a free engineering review to confirm your grade, finish, and tolerance callouts before a single chip is cut.<\/p>\n\n<div class=\"wp-block-group has-light-gray-background-color has-background is-layout-constrained wp-container-core-group-is-layout-e86b207e wp-block-group-is-layout-constrained\" style=\"border-color:#1e73be;border-width:2px;padding-top:20px;padding-right:24px;padding-bottom:20px;padding-left:24px\">\n\n\n<h3 class=\"wp-block-heading\">Need Stainless Steel Parts? Get a Quote with Free DFM Review<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">BravoFabs provides precision stainless steel CNC machining, sheet metal fabrication, and welding in 304, 316, 410, and 17-4PH. Our ISO-certified facility in Dongguan, China delivers tight-tolerance stainless components for industrial clients in Germany, the US, and across Europe, with free material selection and finish recommendations on every RFQ.<\/p>\n\n\n\n<div class=\"wp-block-buttons is-layout-flex wp-block-buttons-is-layout-flex\">\n\n<div class=\"wp-block-button\"><a class=\"wp-block-button__link has-white-color has-vivid-cyan-blue-background-color has-text-color has-background wp-element-button\" href=\"https:\/\/bravofabs.com\/contact\/\" style=\"border-radius:6px\">Request a Stainless Steel Quote \u2192<\/a><\/div>\n\n<\/div>\n\n\n<\/div>\n\n\n\n<div class=\"wp-block-group is-layout-constrained wp-container-core-group-is-layout-cbfb3306 wp-block-group-is-layout-constrained\" style=\"border-left-color:#2563eb;border-left-width:4px;border-left-style:solid;background-color:#f0f4ff;margin-top:32px;margin-bottom:0;padding-top:12px;padding-bottom:12px;padding-left:20px;padding-right:24px\">\n\n<h4 class=\"wp-block-heading\" style=\"font-size:15px;font-style:normal;font-weight:700;line-height:1.4;margin-top:0;margin-bottom:8px\">\ud83d\udd17 Related Services &amp; Articles<\/h4>\n\n\n\n<ul class=\"wp-block-list\" style=\"font-size:14px;line-height:1.7;padding-left:18px\">\n<li><strong><a href=\"https:\/\/bravofabs.com\/stainless-steel-fabrication\/\">Stainless Steel Fabrication Services<\/a><\/strong> \u2014 precision CNC machining &amp; sheet metal in 304, 316, 410 &amp; 17-4PH<\/li>\n<li><strong><a href=\"https:\/\/bravofabs.com\/cnc-machining-service\/\">CNC Machining Service<\/a><\/strong> \u2014 tight-tolerance stainless parts with free DFM review<\/li>\n<li><strong><a href=\"https:\/\/bravofabs.com\/sheet-metal-fabrication-services\/\">Sheet Metal Fabrication<\/a><\/strong> \u2014 laser cutting, bending &amp; welding for stainless enclosures &amp; panels<\/li>\n<li><strong><a href=\"https:\/\/bravofabs.com\/tolerance-standards-in-metal-fabrication\/\">Tolerance Standards in Metal Fabrication<\/a><\/strong> \u2014 ISO 2768 &amp; when tight tolerances are worth the cost<\/li>\n<li><strong><a href=\"https:\/\/bravofabs.com\/cnc-machining-aluminum\/\">CNC Machining Aluminum Guide<\/a><\/strong> \u2014 grade comparison, speeds &amp; surface finishes<\/li>\n<\/ul>\n\n<\/div>\n\n<div class=\"rs-section\"><div class=\"rs-container\"><h2>Explore Related Manufacturing Services<\/h2><div class=\"rs-grid\"><div class=\"rs-card\"><a href=\"\/welding-services\/\">Welding Services<\/a><p>TIG, MIG &amp; spot welding for steel, aluminum &amp; stainless.<\/p><\/div><div class=\"rs-card\"><a href=\"\/surface-treatment-services\/\">Surface Treatment Services<\/a><p>Anodizing, powder coating, plating &amp; passivation.<\/p><\/div><\/div><\/div><\/div>","protected":false},"excerpt":{"rendered":"<p>Key Takeaways 304 stainless steel is the workhorse grade for roughly 70% of stainless fabrication projects \u2014 it balances corrosion resistance, weldability, and cost better than any other grade. 316 adds 2\u20133% molybdenum for chloride and chemical resistance, making it the standard for marine, pharmaceutical, and food-processing applications \u2014 at roughly 1.4\u20131.75\u00d7 the material cost [&hellip;]<\/p>\n","protected":false},"author":0,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_seopress_titles_title":"Stainless Steel Guide: 304 vs 316 vs 410 vs 17-4PH | BravoFabs","_seopress_titles_desc":"Compare 304, 316, 410 & 17-4PH stainless grades for CNC machining & sheet metal. Welding methods, passivation ASTM A967, tolerances & real cost factors.","_seopress_robots_index":"","_seopress_robots_follow":"","_seopress_robots_imageindex":"","_seopress_robots_snippet":"","_seopress_robots_primary_cat":"","_seopress_robots_breadcrumbs":"","_seopress_robots_freeze_modified_date":"","_seopress_robots_custom_modified_date":"","_seopress_robots_canonical":"","_seopress_social_fb_title":"","_seopress_social_fb_desc":"","_seopress_social_fb_img":"","_seopress_social_fb_img_attachment_id":0,"_seopress_social_fb_img_width":0,"_seopress_social_fb_img_height":0,"_seopress_social_twitter_title":"","_seopress_social_twitter_desc":"","_seopress_social_twitter_img":"","_seopress_social_twitter_img_attachment_id":0,"_seopress_social_twitter_img_width":0,"_seopress_social_twitter_img_height":0,"_seopress_redirections_value":"","_seopress_redirections_enabled":"","_seopress_redirections_enabled_regex":"","_seopress_redirections_logged_status":"","_seopress_redirections_param":"","_seopress_redirections_type":0,"_seopress_analysis_target_kw":"stainless steel fabrication grades","footnotes":""},"categories":[40],"tags":[],"class_list":["post-2965","post","type-post","status-publish","format-standard","category-knowledge-base"],"_links":{"self":[{"href":"https:\/\/bravofabs.com\/wp-json\/wp\/v2\/posts\/2965","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/bravofabs.com\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/bravofabs.com\/wp-json\/wp\/v2\/types\/post"}],"replies":[{"embeddable":true,"href":"https:\/\/bravofabs.com\/wp-json\/wp\/v2\/comments?post=2965"}],"version-history":[{"count":1,"href":"https:\/\/bravofabs.com\/wp-json\/wp\/v2\/posts\/2965\/revisions"}],"predecessor-version":[{"id":2967,"href":"https:\/\/bravofabs.com\/wp-json\/wp\/v2\/posts\/2965\/revisions\/2967"}],"wp:attachment":[{"href":"https:\/\/bravofabs.com\/wp-json\/wp\/v2\/media?parent=2965"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/bravofabs.com\/wp-json\/wp\/v2\/categories?post=2965"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/bravofabs.com\/wp-json\/wp\/v2\/tags?post=2965"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}