{"id":13656,"date":"2026-07-15T01:58:13","date_gmt":"2026-07-15T01:58:13","guid":{"rendered":"https:\/\/hlh-js.com\/?p=13656"},"modified":"2026-07-15T02:03:31","modified_gmt":"2026-07-15T02:03:31","slug":"abrasive-blasting-stainless-steel-surgical-instruments-deburring-passivation","status":"publish","type":"post","link":"https:\/\/hlh-js.com\/ja\/resource\/blog\/abrasive-blasting-stainless-steel-surgical-instruments-deburring-passivation\/","title":{"rendered":"Abrasive Blasting Stainless Steel Surgical Instruments: Deburring, Matte Finishing, and Passivation Complete Guide"},"content":{"rendered":"<p><script type=\"application\/ld+json\">{\n    \"@context\": \"https:\\\/\\\/schema.org\",\n    \"@graph\": [\n        {\n            \"@type\": \"Article\",\n            \"headline\": \"Abrasive Blasting Stainless Steel Surgical Instruments: Deburring, Matte Finishing, and Passivation Complete Guide\",\n            \"description\": \"Complete material-focused guide to abrasive blasting of stainless steel surgical instruments \\u2014 medical-grade alloys, deburring vs finishing, steel shot vs glass beads, ASTM A967\\\/F86 passivation, autoclave resistance, and corrosion failure prevention.\",\n            \"datePublished\": \"2026-07-13\",\n            \"dateModified\": \"2026-07-13\",\n            \"author\": {\n                \"@type\": \"Organization\",\n                \"name\": \"Jiangsu Henglihong Technology Co., Ltd.\",\n                \"url\": \"https:\\\/\\\/hlh-js.com\\\/\"\n            },\n            \"publisher\": {\n                \"@type\": \"Organization\",\n                \"name\": \"Jiangsu Henglihong Technology Co., Ltd.\",\n                \"logo\": {\n                    \"@type\": \"ImageObject\",\n                    \"url\": \"https:\\\/\\\/hlh-js.com\\\/wp-content\\\/uploads\\\/hlh-logo.png\"\n                }\n            },\n            \"mainEntityOfPage\": {\n                \"@type\": \"WebPage\",\n                \"@id\": \"https:\\\/\\\/hlh-js.com\\\/resource\\\/blog\\\/abrasive-blasting-stainless-steel-surgical-instruments-deburring-passivation\\\/\"\n            }\n        },\n        {\n            \"@type\": \"FAQPage\",\n            \"mainEntity\": [\n                {\n                    \"@type\": \"Question\",\n                    \"name\": \"What stainless steel grades are used for surgical instruments?\",\n                    \"acceptedAnswer\": {\n                        \"@type\": \"Answer\",\n                        \"text\": \"The most common stainless steel grades for surgical instruments are: 316L (austenitic, highest corrosion resistance, used for delicate forceps, needle holders, fine instruments); 304 (austenitic, general purpose, hemostats, retractors, clamps); 420 (martensitic, high hardness after heat treatment, used for scissors and cutting instruments); 440C (martensitic, highest hardness, premium cutting instruments); and 17-4PH (precipitation hardened, high strength for heavy-duty instruments). Each grade has different passivation response and blasting requirements due to chromium content and microstructure differences.\"\n                    }\n                },\n                {\n                    \"@type\": \"Question\",\n                    \"name\": \"When should steel shot be used instead of glass beads on surgical instruments?\",\n                    \"acceptedAnswer\": {\n                        \"@type\": \"Answer\",\n                        \"text\": \"Stainless steel shot (grade 316L preferred) is appropriate for aggressive deburring of heavy instrument bodies where glass beads do not have sufficient impact energy to dislodge machining burrs or weld spatter. Stainless steel shot is used in the deburring step before a final finishing pass with glass beads. However, stainless steel shot must be completely removed before passivation, and any free iron contamination from the shot must be eliminated. Steel shot should not be used on instruments where dimensional tolerance of delicate features (tips, jaw edges) could be affected by the higher impact energy.\"\n                    }\n                },\n                {\n                    \"@type\": \"Question\",\n                    \"name\": \"What is the difference between deburring and finish blasting for surgical instruments?\",\n                    \"acceptedAnswer\": {\n                        \"@type\": \"Answer\",\n                        \"text\": \"Deburring removes machining burrs, flash, and weld spatter \\u2014 it is an aggressive material removal step using coarser media (glass beads #8\\u2013#10 or stainless steel shot) at higher pressure (2.5\\u20134 bar) to dislodge or break off elevated features. Finish blasting produces the uniform matte surface finish \\u2014 it uses fine media (glass beads #10\\u2013#13) at lower pressure (1.5\\u20132.5 bar) to create the anti-glare texture without removing significant material. Both steps may be required for instruments with burrs, but finish blasting alone is sufficient for cleanly machined instrument bodies.\"\n                    }\n                },\n                {\n                    \"@type\": \"Question\",\n                    \"name\": \"Why does 420-grade stainless steel require different passivation than 316L?\",\n                    \"acceptedAnswer\": {\n                        \"@type\": \"Answer\",\n                        \"text\": \"420 martensitic stainless steel has lower chromium content (~13%) than 316L austenitic (~16\\u201318%) and no molybdenum, making it inherently less corrosion resistant. ASTM A967 specifies different passivation conditions for martensitic stainless steels \\u2014 typically using dilute nitric acid at room temperature (Practice A: 20\\u201325% HNO\\u2083, 21\\u201332\\u00b0C) rather than the higher-concentration, higher-temperature conditions used for austenitic grades. Over-aggressive passivation of martensitic grades can cause surface staining or etching. Citric acid passivation (ASTM A967 Practice E) is generally safer for martensitic grades and has become the preferred method in many instrument manufacturers' processes.\"\n                    }\n                },\n                {\n                    \"@type\": \"Question\",\n                    \"name\": \"How many autoclave cycles should glass bead blasted surgical instruments withstand?\",\n                    \"acceptedAnswer\": {\n                        \"@type\": \"Answer\",\n                        \"text\": \"Properly glass bead blasted and passivated 316L stainless steel surgical instruments should withstand hundreds to over a thousand autoclave sterilization cycles (134\\u00b0C saturated steam, 3 bar, 18 minutes per cycle) without significant corrosion, pitting, or discoloration. The actual service life depends on the alloy grade, passivation quality, handling between uses, and the aggressiveness of cleaning detergents used in pre-sterilization cleaning. Instruments showing rust staining, pitting, or discoloration after fewer than 200 cycles typically indicate inadequate passivation, detergent-induced chloride corrosion, or contamination from dissimilar metals in the same sterilization load.\"\n                    }\n                }\n            ]\n        }\n    ]\n}<\/script> <style>\r\n.hlh-ss*,.hlh-ss*::before,.hlh-ss*::after{box-sizing:border-box;margin:0;padding:0}\r\n.hlh-ss{font-family:'Segoe UI',Arial,sans-serif;font-size:16px;line-height:1.78;color:#1e2a38;max-width:860px;margin:0 auto;padding:0 20px 64px}\r\n.hlh-ss h1{font-size:clamp(1.65rem,3.5vw,2.2rem);font-weight:800;color:#1a3456;line-height:1.22;margin-bottom:20px}\r\n.hlh-ss h2{font-size:clamp(1.18rem,2.5vw,1.46rem);font-weight:700;color:#1a3456;border-left:4px solid #d86e18;padding-left:14px;margin:50px 0 16px}\r\n.hlh-ss h3{font-size:1.05rem;font-weight:700;color:#1a3456;margin:28px 0 10px}\r\n.hlh-ss p{margin-bottom:16px}\r\n.hlh-ss ul,.hlh-ss 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.hlh-ss-faq-icon{transform:rotate(45deg)}\r\n.hlh-ss-faq-answer{overflow:hidden;max-height:0;transition:max-height .32s ease}\r\n.hlh-ss-faq-answer p{padding-bottom:18px;font-size:.93rem;color:#334455;margin:0}\r\n.hlh-ss-cta{background:linear-gradient(135deg,#1a3456,#234572);color:#fff;border-radius:10px;padding:38px 34px;text-align:center;margin-top:56px}\r\n.hlh-ss-cta h2{color:#fff;border:none;padding:0;margin:0 0 12px;font-size:1.4rem}\r\n.hlh-ss-cta p{color:rgba(255,255,255,.85);margin-bottom:24px}\r\n.hlh-ss-cta a{display:inline-block;background:#d86e18;color:#fff;font-weight:700;padding:13px 30px;border-radius:5px;font-size:.96rem;text-decoration:none}\r\n.hlh-ss-cta a:hover{background:#b85c12;text-decoration:none}\r\n@media(max-width:600px){.hlh-ss-hero,.hlh-ss-cta{padding:26px 18px}}\r\n<\/style><\/p>\r\n<div class=\"hlh-ss\"><a class=\"hlh-ss-back\" href=\"https:\/\/hlh-js.com\/resource\/blog\/abrasive-blasting-surface-treatment-medical-devices\/\" target=\"_blank\" rel=\"noopener noreferrer\">\u2190 Abrasive Blasting for Medical Devices: Complete Guide<\/a>\r\n<h1>Abrasive Blasting Stainless Steel Surgical Instruments: Deburring, Matte Finishing, and Passivation Complete Guide<\/h1>\r\n<div class=\"hlh-ss-hero\">\r\n<div class=\"hlh-ss-hero-tag\">In-Depth Guide \u00b7 Medical Device Series \u00b7 C07<\/div>\r\n<p>Stainless steel surgical instruments represent the most mature and highest-volume application of abrasive blasting in medical device manufacturing. The global surgical instrument manufacturing industry \u2014 concentrated in Germany, Pakistan, and the United States \u2014 produces hundreds of millions of instruments annually, and virtually every one passes through a blasting step before passivation. This guide focuses on the stainless steel material science that determines how different instrument grades respond to blasting, how to choose between deburring and finish blasting sequences, why passivation chemistry must match the alloy grade, and how to identify and prevent the corrosion failure modes that cut short instrument service life.<\/p>\r\n<\/div>\r\n<nav class=\"hlh-ss-toc\" aria-label=\"\u76ee\u6b21\">\r\n<div class=\"hlh-ss-toc-label\">Table of Contents<\/div>\r\n<ol>\r\n<li><a href=\"#ss-alloys\">Medical-Grade Stainless Steel Alloys and Their Properties<\/a><\/li>\r\n<li><a href=\"#ss-deburr\">Deburring Stainless Steel Instruments: Steel Shot vs Glass Beads<\/a><\/li>\r\n<li><a href=\"#ss-finish\">Finish Blasting: Achieving the Matte Surface Specification<\/a><\/li>\r\n<li><a href=\"#ss-passivation\">Passivation by Alloy Grade: ASTM A967 Practice Selection<\/a><\/li>\r\n<li><a href=\"#ss-autoclave\">Autoclave Resistance and Long-Term Corrosion Performance<\/a><\/li>\r\n<li><a href=\"#ss-failures\">Corrosion Failure Modes and How Blasting Prevents Them<\/a><\/li>\r\n<li><a href=\"#ss-faq\">\u3088\u304f\u3042\u308b\u8cea\u554f<\/a><\/li>\r\n<\/ol>\r\n<\/nav>\r\n<h2 id=\"ss-alloys\">1. Medical-Grade Stainless Steel Alloys and Their Properties<\/h2>\r\n<div class=\"hlh-ss-table-wrap\">\r\n<table class=\"hlh-ss-table\">\r\n<thead>\r\n<tr>\r\n<th>Grade<\/th>\r\n<th>\u30bf\u30a4\u30d7<\/th>\r\n<th>Cr %<\/th>\r\n<th>Ni %<\/th>\r\n<th>Mo %<\/th>\r\n<th>Hardness (typical)<\/th>\r\n<th>Key Applications<\/th>\r\n<\/tr>\r\n<\/thead>\r\n<tbody>\r\n<tr>\r\n<td>316L<\/td>\r\n<td>Austenitic<\/td>\r\n<td>16\u201318<\/td>\r\n<td>10\u201314<\/td>\r\n<td>2\u20133<\/td>\r\n<td>150\u2013200 HV<\/td>\r\n<td>Forceps, needle holders, delicate instruments, implant trays<\/td>\r\n<\/tr>\r\n<tr>\r\n<td>304<\/td>\r\n<td>Austenitic<\/td>\r\n<td>18\u201320<\/td>\r\n<td>8\u201310.5<\/td>\r\n<td>\u2014<\/td>\r\n<td>150\u2013190 HV<\/td>\r\n<td>Hemostats, retractors, general-purpose clamps<\/td>\r\n<\/tr>\r\n<tr>\r\n<td>420<\/td>\r\n<td>Martensitic<\/td>\r\n<td>12\u201314<\/td>\r\n<td>\u2014<\/td>\r\n<td>\u2014<\/td>\r\n<td>200\u2013650 HV (HT)<\/td>\r\n<td>Scissors, scalpel handles, cutting instruments<\/td>\r\n<\/tr>\r\n<tr>\r\n<td>440C<\/td>\r\n<td>Martensitic<\/td>\r\n<td>16\u201318<\/td>\r\n<td>\u2014<\/td>\r\n<td>0.75<\/td>\r\n<td>650\u2013750 HV (HT)<\/td>\r\n<td>Premium surgical scissors, bone cutters<\/td>\r\n<\/tr>\r\n<tr>\r\n<td>17-4PH<\/td>\r\n<td>Precip. hardened<\/td>\r\n<td>15\u201317.5<\/td>\r\n<td>3\u20135<\/td>\r\n<td>\u2014<\/td>\r\n<td>380\u2013440 HV (H900)<\/td>\r\n<td>High-strength heavy-duty instruments, orthopedic tools<\/td>\r\n<\/tr>\r\n<\/tbody>\r\n<\/table>\r\n<\/div>\r\n<p>The distinction between austenitic (304, 316L) and martensitic (420, 440C) stainless steel grades is fundamental to blasting and passivation practice. Austenitic grades are non-magnetic, relatively soft, and have high chromium and nickel content that provides excellent corrosion resistance. They respond uniformly to glass bead blasting and are passivated with standard nitric or citric acid methods. Martensitic grades are magnetic, heat-treatable to very high hardness, but have lower chromium content and no molybdenum \u2014 making them intrinsically less corrosion resistant than austenitic grades. Their higher hardness means they require higher blasting pressure or longer dwell time to achieve equivalent Ra, and their passivation requires more careful chemistry selection to avoid surface damage.<\/p>\r\n<h2 id=\"ss-deburr\">2. Deburring Stainless Steel Instruments: Steel Shot vs Glass Beads<\/h2>\r\n<p>Deburring removes the sharp metal protrusions \u2014 burrs \u2014 left by machining, stamping, drilling, and welding operations. Burrs on surgical instruments are a patient safety risk (they can catch tissue or gloves), an assembly problem (they prevent jaws from closing precisely), and a sterilization problem (they trap organic debris that resists cleaning).<\/p>\r\n<p>Two blasting approaches address deburring in instrument manufacturing:<\/p>\r\n<p><strong>Stainless steel shot deburring:<\/strong> 304 or 316L stainless steel shot (0.3\u20130.6 mm diameter) at 3\u20135 bar in a rotary blasting machine provides the impact energy needed to mechanically break off or flatten stainless steel burrs on instrument bodies. Steel shot is significantly harder and denser than glass beads, delivering much more impact energy per particle. It is appropriate for aggressive burr removal on instrument bodies, weld seams, and stamped edges. It must be composed of corrosion-resistant stainless steel (not carbon steel) to avoid iron contamination, and all shot residue must be removed before passivation. Steel shot blasting should not be used near precision instrument features \u2014 jaw tips, cutting edges, spring pivots \u2014 where the high impact energy could deform critical geometry.<\/p>\r\n<p><strong>Glass bead deburring:<\/strong> Coarser glass beads (#8\u2013#10, 150\u2013300 \u03bcm) at 2.5\u20133.5 bar can remove light machining burrs and flash from stainless steel instrument surfaces without the risk of over-deforming delicate features. For instruments with fine features and light burrs, glass beads alone in a two-step process (coarser grade for deburring, finer grade for finish) eliminate the need for steel shot and simplify the process and cleaning requirements.<\/p>\r\n<div class=\"hlh-ss-callout\"><strong>Steel shot contamination rule:<\/strong> Carbon steel shot must never be used on stainless steel surgical instruments. Carbon steel particles embedded in the stainless steel surface or remaining as residue will corrode in the autoclave environment, creating rust staining and potentially driving pitting corrosion into the instrument body. Only 304 or 316L stainless steel shot or glass beads are acceptable media for stainless surgical instrument blasting.<\/div>\r\n<h2 id=\"ss-finish\">3. Finish Blasting: Achieving the Matte Surface Specification<\/h2>\r\n<p>After deburring (if required), finish blasting with fine glass beads produces the matte finish required for anti-glare performance and passivation preparation. The target Ra for surgical instrument matte finish is typically 0.4\u20131.6 \u03bcm, with the exact specification set by the instrument design requirements and customer\/regulatory standards.<\/p>\r\n<div class=\"hlh-ss-table-wrap\">\r\n<table class=\"hlh-ss-table\">\r\n<thead>\r\n<tr>\r\n<th>Instrument Category<\/th>\r\n<th>Grade<\/th>\r\n<th>Finish Bead Grade<\/th>\r\n<th>Pressure<\/th>\r\n<th>Target Ra<\/th>\r\n<\/tr>\r\n<\/thead>\r\n<tbody>\r\n<tr>\r\n<td>General hemostats and clamps<\/td>\r\n<td>304, 316L<\/td>\r\n<td>#10\u2013#12<\/td>\r\n<td>2.0\u20132.5 bar<\/td>\r\n<td>0.6\u20131.2 \u03bcm<\/td>\r\n<\/tr>\r\n<tr>\r\n<td>Delicate microsurgical forceps<\/td>\r\n<td>316L<\/td>\r\n<td>#12\u2013#13<\/td>\r\n<td>1.5\u20132.0 bar<\/td>\r\n<td>0.4\u20130.8 \u03bcm<\/td>\r\n<\/tr>\r\n<tr>\r\n<td>Scissors body (non-cutting surfaces)<\/td>\r\n<td>420, 440C<\/td>\r\n<td>#10\u2013#12<\/td>\r\n<td>2.5\u20133.0 bar<\/td>\r\n<td>0.6\u20131.2 \u03bcm<\/td>\r\n<\/tr>\r\n<tr>\r\n<td>Retractors and large instruments<\/td>\r\n<td>304<\/td>\r\n<td>#8\u2013#10<\/td>\r\n<td>2.5\u20133.5 bar<\/td>\r\n<td>0.8\u20131.6 \u03bcm<\/td>\r\n<\/tr>\r\n<tr>\r\n<td>High-strength orthopedic instruments<\/td>\r\n<td>17-4PH<\/td>\r\n<td>#10<\/td>\r\n<td>2.5\u20133.5 bar<\/td>\r\n<td>0.6\u20131.4 \u03bcm<\/td>\r\n<\/tr>\r\n<\/tbody>\r\n<\/table>\r\n<\/div>\r\n<p>For martensitic grades (420, 440C), higher hardness compared to austenitic grades means more pressure is required to achieve equivalent Ra. This is important because scissors and cutting instruments made from 420 or 440C must have their cutting edge geometry masking confirmed before finish blasting \u2014 the higher pressure needed for the harder alloy body would dull or round a precision ground cutting edge if unprotected.<\/p>\r\n<h2 id=\"ss-passivation\">4. Passivation by Alloy Grade: ASTM A967 Practice Selection<\/h2>\r\n<p>Passivation treatment must be matched to the stainless steel grade being treated. Using the wrong passivation conditions for a grade can either fail to adequately restore the passive layer (under-treatment) or damage the surface through over-etching or intergranular attack (over-treatment).<\/p>\r\n<div class=\"hlh-ss-table-wrap\">\r\n<table class=\"hlh-ss-table\">\r\n<thead>\r\n<tr>\r\n<th>Alloy Grade<\/th>\r\n<th>Recommended ASTM A967 Practice<\/th>\r\n<th>Typical Conditions<\/th>\r\n<th>Notes<\/th>\r\n<\/tr>\r\n<\/thead>\r\n<tbody>\r\n<tr>\r\n<td>316L, 304 (austenitic)<\/td>\r\n<td>Practice B or C (nitric) or E\/F (citric)<\/td>\r\n<td>20\u201340% HNO\u2083, 48\u201355\u00b0C, 30 min; or 4\u201310% citric, 54\u201365\u00b0C, 20 min<\/td>\r\n<td>Higher temp nitric or citric effective; citric preferred for environmental reasons<\/td>\r\n<\/tr>\r\n<tr>\r\n<td>420 (martensitic, annealed)<\/td>\r\n<td>Practice A (nitric, mild)<\/td>\r\n<td>20\u201325% HNO\u2083, 21\u201332\u00b0C, 30 min<\/td>\r\n<td>Avoid high temp nitric \u2014 can cause intergranular attack; citric Practice E safe<\/td>\r\n<\/tr>\r\n<tr>\r\n<td>440C (martensitic, hardened)<\/td>\r\n<td>Practice A or E (mild citric)<\/td>\r\n<td>20% HNO\u2083, 21\u00b0C, 30 min; or 4% citric, 21\u00b0C, 30 min<\/td>\r\n<td>Very conservative conditions to protect hardened surface from etching<\/td>\r\n<\/tr>\r\n<tr>\r\n<td>17-4PH (aged condition)<\/td>\r\n<td>Practice B or E<\/td>\r\n<td>20\u201340% HNO\u2083, 48\u00b0C, 20 min; or citric Practice E<\/td>\r\n<td>Similar to austenitic response in aged H900\/H1025 condition<\/td>\r\n<\/tr>\r\n<\/tbody>\r\n<\/table>\r\n<\/div>\r\n<h2 id=\"ss-autoclave\">5. Autoclave Resistance and Long-Term Corrosion Performance<\/h2>\r\n<p>Surgical instrument autoclave sterilization (134\u00b0C saturated steam, approximately 3 bar pressure, 3\u201318 minutes per cycle depending on the cycle type) is a harsh corrosion test repeated hundreds of times over instrument service life. The combination of elevated temperature, high humidity, chloride ions from detergent residues, and frequent thermal cycling creates conditions that aggressively test passivation quality.<\/p>\r\n<p>Well-blasted and passivated 316L instruments routinely survive 500\u20131000+ autoclave cycles without significant corrosion. The critical factors are:<\/p>\r\n<ul>\r\n<li><strong>Freedom from iron contamination<\/strong> at the surface after blasting. Any carbon steel or free iron from blasting media or equipment will corrode in the autoclave and seed pitting corrosion into the surrounding stainless matrix.<\/li>\r\n<li><strong>Complete passivation layer formation<\/strong> verified by copper sulfate or ferroxyl test.<\/li>\r\n<li><strong>Avoidance of chloride concentrations<\/strong> from detergent residues. Most instrument damage attributed to autoclaving is actually caused by chloride-containing detergent residues not fully rinsed from instrument surfaces before sterilization.<\/li>\r\n<li><strong>Avoidance of dissimilar metal contact<\/strong> in the sterilization load. Carbon steel instruments or carbon steel instrument stands in the same autoclave load can seed galvanic corrosion on stainless instruments.<\/li>\r\n<\/ul>\r\n<h2 id=\"ss-failures\">6. Corrosion Failure Modes and How Blasting Prevents Them<\/h2>\r\n<p><strong>Pitting corrosion<\/strong> \u2014 small, deep craters that develop on the instrument surface, typically originating at surface impurities, scratches, or free iron contamination \u2014 is the most common corrosion failure in stainless steel instruments. Glass bead blasting removes the Beilby surface layer and machining-embedded contamination that serves as pit initiation sites, and passivation rebuilds the protective oxide that suppresses pit initiation electrochemically.<\/p>\r\n<p><strong>Crevice corrosion<\/strong> occurs in tight gaps between mating surfaces (instrument box-joint crevices, screw holes, tissue-grasping serrations) where stagnant electrolyte and oxygen depletion create an aggressive local electrochemical environment. Blasting cannot directly prevent crevice corrosion, but thorough post-blast cleaning of these crevices ensures no residue traps chloride-containing solution that would accelerate the process.<\/p>\r\n<p><strong>Stress corrosion cracking (SCC)<\/strong> occurs in austenitic stainless steel under tensile stress in the presence of chloride ions. Glass bead blasting introduces compressive surface stresses that directly oppose SCC initiation by eliminating the surface tensile stress state that machining creates \u2014 this is one of the most practically important benefits of bead blasting for instruments with spring-loaded jaws or curved bodies under tensile bending stress.<\/p>\r\n<div class=\"hlh-ss-related\">\r\n<h3>Related Guides in This Series<\/h3>\r\n<a href=\"https:\/\/hlh-js.com\/resource\/blog\/glass-bead-blasting-surgical-instruments-matte-finish-passivation\/\" target=\"_blank\" rel=\"noopener noreferrer\">\u2192 Glass Bead Blasting for Surgical Instruments: Anti-Glare Finish Guide<\/a> <a href=\"https:\/\/hlh-js.com\/resource\/blog\/abrasive-media-medical-device-blasting-glass-beads-aluminum-oxide-tio2-zirconia-comparison\/\" target=\"_blank\" rel=\"noopener noreferrer\">\u2192 Abrasive Media Comparison for Medical Device Blasting<\/a> <a href=\"https:\/\/hlh-js.com\/resource\/blog\/abrasive-blasting-surface-treatment-medical-devices\/\" target=\"_blank\" rel=\"noopener noreferrer\">\u2190 Complete Guide: Abrasive Blasting for Medical Devices<\/a><\/div>\r\n<h2 id=\"ss-faq\">7. Frequently Asked Questions<\/h2>\r\n<div>\r\n<div class=\"hlh-ss-faq-item\"><button class=\"hlh-ss-faq-btn\" aria-expanded=\"false\" aria-controls=\"ssq1\">What stainless steel grades are used for surgical instruments?<span class=\"hlh-ss-faq-icon\">+<\/span><\/button>\r\n<div id=\"ssq1\" class=\"hlh-ss-faq-answer\">\r\n<p>316L (best corrosion resistance; delicate forceps, needle holders), 304 (general purpose; hemostats, retractors), 420 (hardened martensitic; scissors and cutting instruments), 440C (highest hardness; premium cutting instruments), and 17-4PH (precipitation hardened; heavy-duty orthopedic instruments). Each grade has different hardness, chromium content, and corrosion resistance affecting blasting and passivation requirements.<\/p>\r\n<\/div>\r\n<\/div>\r\n<div class=\"hlh-ss-faq-item\"><button class=\"hlh-ss-faq-btn\" aria-expanded=\"false\" aria-controls=\"ssq2\">When should steel shot be used instead of glass beads?<span class=\"hlh-ss-faq-icon\">+<\/span><\/button>\r\n<div id=\"ssq2\" class=\"hlh-ss-faq-answer\">\r\n<p>316L stainless steel shot is appropriate for aggressive deburring of heavy instrument bodies with significant machining burrs or weld spatter that glass beads cannot remove at safe pressures. Steel shot must be completely removed before passivation. It must never be carbon steel (only 304\/316L), and it should not be used near precision features where high impact energy could deform critical geometry. Many manufacturers prefer two-pass glass bead processes (coarse then fine) to avoid steel shot entirely.<\/p>\r\n<\/div>\r\n<\/div>\r\n<div class=\"hlh-ss-faq-item\"><button class=\"hlh-ss-faq-btn\" aria-expanded=\"false\" aria-controls=\"ssq3\">What is the difference between deburring and finish blasting?<span class=\"hlh-ss-faq-icon\">+<\/span><\/button>\r\n<div id=\"ssq3\" class=\"hlh-ss-faq-answer\">\r\n<p>Deburring removes machining burrs and flash using coarser media (#8\u2013#10 glass beads or stainless steel shot) at higher pressure (2.5\u20134 bar). Finish blasting produces the uniform matte anti-glare surface using fine media (#10\u2013#13 glass beads) at lower pressure (1.5\u20132.5 bar). Both steps are required for instruments with significant burrs; finish blasting alone is sufficient for cleanly machined bodies.<\/p>\r\n<\/div>\r\n<\/div>\r\n<div class=\"hlh-ss-faq-item\"><button class=\"hlh-ss-faq-btn\" aria-expanded=\"false\" aria-controls=\"ssq4\">Why does 420-grade stainless require different passivation than 316L?<span class=\"hlh-ss-faq-icon\">+<\/span><\/button>\r\n<div id=\"ssq4\" class=\"hlh-ss-faq-answer\">\r\n<p>420 martensitic stainless has lower chromium (~13%) and no molybdenum, making it less corrosion resistant and more sensitive to aggressive passivation chemistry. ASTM A967 Practice A (dilute nitric acid at room temperature) or Practice E (citric acid) are recommended \u2014 aggressive high-temperature nitric acid conditions used for austenitic grades can cause intergranular attack on martensitic microstructures. Citric acid passivation is particularly safe for 420 and 440C grades.<\/p>\r\n<\/div>\r\n<\/div>\r\n<div class=\"hlh-ss-faq-item\"><button class=\"hlh-ss-faq-btn\" aria-expanded=\"false\" aria-controls=\"ssq5\">How many autoclave cycles should blasted\/passivated instruments withstand?<span class=\"hlh-ss-faq-icon\">+<\/span><\/button>\r\n<div id=\"ssq5\" class=\"hlh-ss-faq-answer\">\r\n<p>Properly blasted and passivated 316L instruments should withstand 500\u20131000+ autoclave sterilization cycles without significant corrosion. Failures below 200 cycles typically indicate inadequate passivation, carbon steel contamination from blasting media, detergent-induced chloride corrosion from incomplete pre-sterilization rinse, or dissimilar metal contact with carbon steel instruments in the same load.<\/p>\r\n<\/div>\r\n<\/div>\r\n<\/div>\r\n<div class=\"hlh-ss-cta\">\r\n<h2>Source Glass Beads and SS Shot for Surgical Instrument Finishing<\/h2>\r\n<p>Jiangsu Henglihong Technology supplies glass beads in medical instrument grades and stainless steel shot for deburring, with full material certifications and size distribution data for process validation.<\/p>\r\n<a href=\"https:\/\/hlh-js.com\/contact\/\" target=\"_blank\" rel=\"noopener noreferrer\">Request Specifications &amp; Quote<\/a><\/div>\r\n<\/div>\r\n<p><script>(function(){var b=document.querySelectorAll('.hlh-ss-faq-btn');b.forEach(function(btn){btn.addEventListener('click',function(){var e=this.getAttribute('aria-expanded')==='true',a=document.getElementById(this.getAttribute('aria-controls'));b.forEach(function(x){x.setAttribute('aria-expanded','false');var y=document.getElementById(x.getAttribute('aria-controls'));if(y)y.style.maxHeight='0'});if(!e){this.setAttribute('aria-expanded','true');a.style.maxHeight=a.scrollHeight+'px'}})})})();<\/script><\/p>","protected":false},"excerpt":{"rendered":"<p>\u2190 Abrasive Blasting for Medical Devices: Complete Guide Abrasive Blasting  [&#8230;]<\/p>","protected":false},"author":1,"featured_media":13658,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[62,175,138],"tags":[],"class_list":["post-13656","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-blog","category-industry","category-resource"],"_links":{"self":[{"href":"https:\/\/hlh-js.com\/ja\/wp-json\/wp\/v2\/posts\/13656","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/hlh-js.com\/ja\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/hlh-js.com\/ja\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/hlh-js.com\/ja\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/hlh-js.com\/ja\/wp-json\/wp\/v2\/comments?post=13656"}],"version-history":[{"count":3,"href":"https:\/\/hlh-js.com\/ja\/wp-json\/wp\/v2\/posts\/13656\/revisions"}],"predecessor-version":[{"id":13686,"href":"https:\/\/hlh-js.com\/ja\/wp-json\/wp\/v2\/posts\/13656\/revisions\/13686"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/hlh-js.com\/ja\/wp-json\/wp\/v2\/media\/13658"}],"wp:attachment":[{"href":"https:\/\/hlh-js.com\/ja\/wp-json\/wp\/v2\/media?parent=13656"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/hlh-js.com\/ja\/wp-json\/wp\/v2\/categories?post=13656"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/hlh-js.com\/ja\/wp-json\/wp\/v2\/tags?post=13656"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}