{"id":13976,"date":"2026-08-05T06:11:16","date_gmt":"2026-08-05T06:11:16","guid":{"rendered":"https:\/\/hlh-js.com\/?p=13976"},"modified":"2026-08-05T06:11:16","modified_gmt":"2026-08-05T06:11:16","slug":"surface-roughness-measurement-for-abrasively-finished-titanium-slm-parts-ra-sa-and-industry-specifications","status":"publish","type":"post","link":"https:\/\/hlh-js.com\/zh\/resource\/blog\/surface-roughness-measurement-for-abrasively-finished-titanium-slm-parts-ra-sa-and-industry-specifications\/","title":{"rendered":"Surface Roughness Measurement for Abrasively Finished Titanium SLM Parts: Ra, Sa, and Industry Specifications"},"content":{"rendered":"<!-- hlh-tis-c11.html | Jiangsu Henglihong Technology Co., Ltd. | August 2026 -->\n<style>\n.hlh-tis*,.hlh-tis*::before,.hlh-tis*::after{box-sizing:border-box;margin:0;padding:0}\n.hlh-tis{font-family:-apple-system,BlinkMacSystemFont,'Segoe UI',Roboto,'Helvetica 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measurement instruments, cut-off wavelength selection, and industry specification tables by application.\",\n            \"url\": \"https:\\\/\\\/hlh-js.com\\\/resource\\\/blog\\\/surface-roughness-measurement-for-abrasively-finished-titanium-slm-parts-ra-sa-and-industry-specifications\\\/\",\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                \"url\": \"https:\\\/\\\/hlh-js.com\"\n            },\n            \"datePublished\": \"2026-08-01\",\n            \"dateModified\": \"2026-08-01\"\n        },\n        {\n            \"@type\": \"FAQPage\",\n            \"mainEntity\": [\n                {\n                    \"@type\": \"Question\",\n                    \"name\": \"Should I measure Ra before and after each blast pass, or only at the end?\",\n                    \"acceptedAnswer\": {\n                        \"@type\": \"Answer\",\n                        \"text\": \"For production runs of qualified parts, Ra measurement after the final stage is sufficient if the process is validated and all parameters are controlled within the validated limits. For first-article runs, measure after each blast stage to build the Ra-reduction curve for the specific part and process \\u2014 this data becomes the validation evidence and tells you exactly which stage achieves the specification. Measure after Stage 1 (coarse roughness normalization) to confirm the Stage 1 target is met before committing to Stage 2, and measure after Stage 2 to confirm whether Stage 3 (precision finish) is needed. In-process measurement prevents both over-blasting (if Stage 2 already meets the final specification) and under-blasting (if Ra after Stage 2 is above target).\"\n                    }\n                },\n                {\n                    \"@type\": \"Question\",\n                    \"name\": \"What measurement instrument is recommended for titanium SLM lattice structures?\",\n                    \"acceptedAnswer\": {\n                        \"@type\": \"Answer\",\n                        \"text\": \"Contact profilometers cannot access internal lattice strut surfaces and cannot measure strut curvature accurately. For external lattice surfaces with cell openings above 500 \\u03bcm, optical CSI at low magnification (5\\u201310\\u00d7 objective, field of view 1\\u20132 mm) can characterize accessible strut surfaces when positioned correctly. For fully internal lattice surfaces that cannot be optically accessed, representative characterization requires: (1) sectioning a sacrificial coupon of the same build and measuring cross-section surface topography by contact or optical profilometry, or (2) replicating the internal surface with low-viscosity epoxy (replica method) and measuring the cured replica surface. Method (1) is more commonly used in production qualification of implant lattice structures.\"\n                    }\n                },\n                {\n                    \"@type\": \"Question\",\n                    \"name\": \"How do I set the cut-off wavelength for measuring blasted titanium SLM surfaces?\",\n                    \"acceptedAnswer\": {\n                        \"@type\": \"Answer\",\n                        \"text\": \"Per ISO 4288: Ra 0.1\\u20132 \\u03bcm \\u2192 \\u03bbc = 0.8 mm (assessment length 4.0 mm); Ra 2\\u201310 \\u03bcm \\u2192 \\u03bbc = 2.5 mm (assessment length 12.5 mm). For blasted titanium SLM in the Ra 1\\u20135 \\u03bcm range, use \\u03bbc = 0.8 mm as the primary choice. A practical check: if the Ra value changes by more than 20% when you switch from \\u03bbc = 0.8 mm to 2.5 mm, the surface has significant mid-range wavelength content (residual staircase periodicity or waviness from the SLM scan pattern) that is being filtered differently. Report the \\u03bbc value alongside Ra in all measurement records so results are comparable between instruments and operators.\"\n                    }\n                },\n                {\n                    \"@type\": \"Question\",\n                    \"name\": \"Can I use the same Ra specification for medical and aerospace titanium SLM parts?\",\n                    \"acceptedAnswer\": {\n                        \"@type\": \"Answer\",\n                        \"text\": \"Not without application-specific review. Medical implant surfaces target Ra 1.0\\u20133.0 \\u03bcm for osseointegration \\u2014 this range is biologically optimized for bone cell response and is not derived from any mechanical performance requirement. Aerospace structural surfaces target Ra 1.6\\u20133.2 \\u03bcm after shot peening, which reflects the peening process outcome, not a mechanical optimum per se. PVD coating substrates need Ra 0.4\\u20131.6 \\u03bcm for adhesion reasons. These specifications overlap in the Ra 1.6\\u20133.0 \\u03bcm range, but the meaning and the measurement protocol (which parameters, which instrument, which locations) differ between applications. Always derive the Ra specification from the engineering requirement for the specific application, not from a generic blasting specification.\"\n                    }\n                }\n            ]\n        }\n    ]\n}<\/script>\n<div class=\"hlh-tis\">\n<a class=\"c-back\" href=\"https:\/\/hlh-js.com\/resource\/blog\/abrasive-finishing-titanium-slm-parts-complete-guide\/\" target=\"_blank\" rel=\"noopener noreferrer\">&#8592; Complete Guide: Abrasive Finishing for Titanium SLM Parts<\/a>\n<h1>Surface Roughness Measurement for Abrasively Finished Titanium SLM Parts: Ra, Sa, and Industry Specifications<\/h1>\n<div class=\"c-meta\">\n  <span><strong>\u7531<\/strong> \u6c5f\u82cf\u6052\u5229\u5b8f\u79d1\u6280\u80a1\u4efd\u6709\u9650\u516c\u53f8<\/span>\n  <span><strong>Updated:<\/strong> August 2026<\/span>\n  <span><strong>Topic:<\/strong> Titanium SLM surface roughness Ra Sa measurement abrasively finished<\/span>\n<\/div>\n<p class=\"c-lead\">Ra is the universal starting point for surface roughness specification on titanium SLM parts \u2014 but it is rarely the whole story. As-blasted SLM surfaces are isotropic and topographically complex; a single Ra value can describe surfaces that behave completely differently in fatigue, coating adhesion, and osseointegration. This guide covers the complete measurement framework: which parameters to specify, which instruments to use, how to set up the measurement protocol, and what the industry specifications actually require for each major titanium SLM application.<\/p>\n<nav class=\"c-toc\" aria-label=\"Table of Contents\">\n  <div class=\"c-toc-title\">Table of Contents<\/div>\n  <ol>\n    <li><a href=\"#sec-why\">Why Ra Alone Is Insufficient for Blasted SLM Surfaces<\/a><\/li>\n    <li><a href=\"#sec-2d\">2D Profile Parameters: Ra, Rz, Rsk, and What They Reveal<\/a><\/li>\n    <li><a href=\"#sec-3d\">3D Areal Parameters: ISO 25178 \u2014 Sa, Sz, Sdr, Smr<\/a><\/li>\n    <li><a href=\"#sec-instruments\">Measurement Instruments: Contact vs. Optical Methods<\/a><\/li>\n    <li><a href=\"#sec-protocol\">Setting Up the Measurement Protocol<\/a><\/li>\n    <li><a href=\"#sec-specs\">Industry Specification Tables by Application<\/a><\/li>\n    <li><a href=\"#sec-faq\">Frequently Asked Questions<\/a><\/li>\n  <\/ol>\n<\/nav>\n\n<h2 id=\"sec-why\">1. Why Ra Alone Is Insufficient for Blasted SLM Surfaces<\/h2>\n<p>The arithmetical mean roughness Ra is the most widely cited surface parameter in engineering drawings and industry standards. It averages the absolute height deviations from the mean surface over a defined evaluation length. Ra is useful, standardized, and measured by virtually every profilometer in production service. It is also the least informative single descriptor for a blasted titanium SLM surface, for three reasons.<\/p>\n<p>First, Ra is insensitive to the distribution of heights. A surface with deep, narrow valleys and flat plateaus (characteristic of incompletely blasted staircase steps) can report the same Ra as a surface with a gentle, uniformly rounded profile (characteristic of a well-blasted surface), even though the two surfaces perform fundamentally differently in fatigue loading, coating adhesion, and biological response. Second, Ra from a 2D line trace is directionally sensitive on SLM surfaces: measured parallel to the build direction, Ra reflects the staircase periodicity; measured perpendicular, Ra reflects the melt track spacing. A single measurement in one direction gives an incomplete picture of the surface. Third, Ra cannot capture the areal features of complex SLM geometries \u2014 curved surfaces, lattice struts, and channel walls cannot be characterized by a straight stylus traverse. This article is part of the series on <a href=\"https:\/\/hlh-js.com\/resource\/blog\/abrasive-finishing-titanium-slm-parts-complete-guide\/\" target=\"_blank\" rel=\"noopener noreferrer\">abrasive finishing for titanium SLM parts<\/a>.<\/p>\n\n<h2 id=\"sec-2d\">2. 2D Profile Parameters: Ra, Rz, Rsk, and What They Reveal<\/h2>\n<p><strong>Ra (arithmetical mean height):<\/strong> The mean absolute deviation of the height profile from the mean line, evaluated over the assessment length. Defined in ISO 4287. Ra is the primary specification parameter for most engineering applications and is the starting point for any surface characterization. Its limitation is described above: it does not distinguish profile shape.<\/p>\n<p><strong>Rz (mean maximum profile height):<\/strong> The average peak-to-valley height across five consecutive sampling lengths. Rz is more sensitive than Ra to individual extreme features \u2014 deep satellite particle craters, sharp staircase-step peaks, or individual media impact craters that represent outlier events in the profile. For fatigue and coating adhesion applications, Rz better predicts behavior because crack nucleation and coating delamination are driven by worst-case surface features rather than average features. Rz is typically 5\u20138&#215; Ra on well-blasted titanium SLM surfaces; on incompletely blasted or staircase-dominated surfaces, the Rz\/Ra ratio may reach 10\u201315&#215;.<\/p>\n<p><strong>Rsk (skewness):<\/strong> The third statistical moment of the height distribution, describing the asymmetry of the profile. A negative Rsk (skewed toward valleys) indicates a surface with flat plateaus and deep valleys \u2014 common on shot-peened surfaces and well-finished titanium. A positive Rsk (skewed toward peaks) indicates a surface with sharp peaks projecting above a flat datum \u2014 characteristic of incompletely blasted staircase surfaces or surfaces with residual satellite particles. Rsk &lt; \u22121 after blasting indicates excellent satellite removal and staircase smoothing; Rsk &gt; 0 after blasting is a flag to investigate whether blasting was adequate.<\/p>\n\n<h2 id=\"sec-3d\">3. 3D Areal Parameters: ISO 25178 \u2014 Sa, Sz, Sdr, Smr<\/h2>\n<p>ISO 25178 defines the 3D (areal) surface texture parameters that extend the 2D profile parameters to area measurements. For titanium SLM surfaces, 3D parameters provide a more complete and representative characterization than single-line 2D profiles:<\/p>\n<ul>\n  <li><strong>Sa (arithmetical mean height, areal):<\/strong> The 3D equivalent of Ra, calculated over a defined measurement area rather than a line. Sa captures the full surface variability including features not sampled by a single profile trace. For medical implant surface characterization, Sa is increasingly required alongside Ra in purchasing specifications and regulatory submissions.<\/li>\n  <li><strong>Sz (maximum height, areal):<\/strong> The distance from the highest peak to the deepest valley over the entire measurement area. Sz identifies the worst-case surface feature and is the most relevant parameter for fatigue crack nucleation risk assessment.<\/li>\n  <li><strong>Sdr (developed interfacial area ratio):<\/strong> Indicates how much the true 3D surface area exceeds the nominal projected area, expressed as a fraction. A blasted titanium SLM surface with Sdr of 0.15 has 15% more true surface area than the projected flat area. Sdr is directly relevant to osseointegration (more surface area = more osteoblast contact sites) and coating adhesion (more bonding area = higher adhesion strength).<\/li>\n  <li><strong>Smr (material ratio):<\/strong> The fraction of the measurement area above a defined height threshold. Used in tribological applications to predict bearing area behavior. For titanium SLM contact surfaces, Smr at defined levels provides a standardized characterization of the plateau structure that determines the actual contact area under load.<\/li>\n<\/ul>\n\n<h2 id=\"sec-instruments\">4. Measurement Instruments: Contact vs. Optical Methods<\/h2>\n<p><strong>Contact profilometry (stylus):<\/strong> A diamond-tipped stylus (2\u20135 &#956;m tip radius) traverses the surface at a defined contact force (0.75\u20131.0 mN for titanium to avoid scratch-induced damage) and records the height profile. Contact profilometers are calibrated to ISO 12179, measure Ra, Rz, and profile parameters accurately on flat and gently curved surfaces, and are the standard for production inspection. Their limitations: single-line trace (misses areal features), cannot measure steep slopes beyond &#177;60\u201370&#176; from horizontal, and the stylus tip radius limits lateral resolution to approximately 2&#215; the tip radius (\u22485\u201310 &#956;m).<\/p>\n<p><strong>Optical coherence scanning interferometry (CSI\/VSI):<\/strong> Non-contact, rapid, capable of measuring step heights from sub-nanometer to several millimeters, and able to characterize complete surface areas rather than single traces. CSI\/VSI instruments measure Sa, Sz, Sdr, and the full ISO 25178 areal parameter set directly. They are the preferred instrument for characterizing complex SLM surfaces, particularly for medical implant qualification where areal parameters are required. Lateral resolution: 0.5\u20132 &#956;m depending on objective magnification. Maximum measureable slope: &#177;70&#176; from horizontal.<\/p>\n<p><strong>Confocal laser scanning microscopy:<\/strong> Provides lateral resolution down to \u22480.2 &#956;m and is used in research and development for detailed characterization of SLA and blasted implant surfaces. Not commonly used in production due to throughput constraints (measurement of a 1 mm&#178; area at full resolution takes 5\u201320 minutes).<\/p>\n<div class=\"c-tbl\">\n<table>\n  <thead><tr><th>Method<\/th><th>Ra Accuracy<\/th><th>3D Areal Parameters<\/th><th>Max Slope<\/th><th>Throughput<\/th><th>Best For<\/th><\/tr><\/thead>\n  <tbody>\n    <tr><td>Contact profilometer<\/td><td>&#177;5\u201310%<\/td><td>No (line only)<\/td><td>&#177;60\u201370&#176;<\/td><td>High (30\u201360s\/meas)<\/td><td>Production Ra QC<\/td><\/tr>\n    <tr><td>Optical CSI\/VSI<\/td><td>&#177;2\u20135%<\/td><td>Yes (full ISO 25178)<\/td><td>&#177;70&#176;<\/td><td>Medium (2\u20135 min\/area)<\/td><td>Implant, R&amp;D qualification<\/td><\/tr>\n    <tr><td>Confocal microscopy<\/td><td>&#177;1\u20133%<\/td><td>Yes (full ISO 25178)<\/td><td>&#177;70&#176;<\/td><td>Low (5\u201320 min\/area)<\/td><td>R&amp;D, implant development<\/td><\/tr>\n  <\/tbody>\n<\/table>\n<\/div>\n\n<h2 id=\"sec-protocol\">5. Setting Up the Measurement Protocol<\/h2>\n<p>A complete surface roughness measurement protocol for titanium SLM finishing specifies: the parameters to be measured (Ra, Rz, Sa, etc.), the measurement instrument and its calibration traceability, the cut-off wavelength (&#955;c) selection, the measurement location and number of replicates per part, and the acceptance criteria (pass\/fail limits for each parameter).<\/p>\n<p><strong>Cut-off wavelength (&#955;c) selection:<\/strong> ISO 4288 provides the standard guidance. For blasted titanium SLM surfaces, the appropriate &#955;c depends on the Ra range: Ra 0.1\u20132 &#956;m &#8594; &#955;c = 0.8 mm (5 sampling lengths = 4 mm evaluation length); Ra 2\u201310 &#956;m &#8594; &#955;c = 2.5 mm (5 sampling lengths = 12.5 mm evaluation length). Using a &#955;c too small for the surface Ra underestimates Ra by excluding relevant wavelengths; too large includes waviness from part geometry rather than surface texture. For most blasted titanium SLM surfaces in the Ra 1\u20136 &#956;m range, &#955;c = 0.8 mm is appropriate for the final finished surface and &#955;c = 2.5 mm for as-built or Stage 1 blast surfaces.<\/p>\n<p><strong>Measurement location selection:<\/strong> Specify measurement locations on the part drawing or a separate measurement plan document. Include at least one location on each functional surface type (upskin, downskin, vertical wall) and at least one location near a geometrically complex feature (corner, fillet, channel edge) where blast coverage may be less uniform. For medical implant batch inspection, a minimum of three measurements per part in defined locations is typical; for aerospace components, the measurement plan is part of the first-article inspection record and is agreed with the customer.<\/p>\n\n<h2 id=\"sec-specs\">6. Industry Specification Tables by Application<\/h2>\n<div class=\"c-tbl\">\n<table>\n  <thead><tr><th>Application<\/th><th>Ra Target<\/th><th>Rz (indicative)<\/th><th>Sa (if specified)<\/th><th>Key Standard<\/th><\/tr><\/thead>\n  <tbody>\n    <tr><td>Osseointegration \u2014 dental (SLA)<\/td><td>1.5\u20133.0 &#956;m<\/td><td>10\u201320 &#956;m<\/td><td>Sa 1.5\u20133.0 &#956;m<\/td><td>ISO 10993, ASTM F1875<\/td><\/tr>\n    <tr><td>Osseointegration \u2014 orthopedic<\/td><td>1.0\u20133.0 &#956;m<\/td><td>8\u201320 &#956;m<\/td><td>Sa 1.0\u20133.0 &#956;m<\/td><td>ISO 10993, ASTM F1537<\/td><\/tr>\n    <tr><td>Aerospace shot-peened structural<\/td><td>1.6\u20133.2 &#956;m<\/td><td>10\u201320 &#956;m<\/td><td>Not typically specified<\/td><td>AMS 2430, drawing callout<\/td><\/tr>\n    <tr><td>PVD coating adhesion<\/td><td>0.4\u20131.6 &#956;m<\/td><td>3\u201310 &#956;m<\/td><td>Not typically specified<\/td><td>Coating system spec<\/td><\/tr>\n    <tr><td>HVOF thermal spray anchor<\/td><td>6\u201312 &#956;m<\/td><td>Rz 50\u2013120 &#956;m<\/td><td>Not specified<\/td><td>AWS C2.18, supplier spec<\/td><\/tr>\n    <tr><td>DLC coating<\/td><td>0.2\u20130.8 &#956;m<\/td><td>1.5\u20136 &#956;m<\/td><td>Not typically specified<\/td><td>PECVD equipment standard<\/td><\/tr>\n    <tr><td>Industrial structural (uncoated)<\/td><td>0.8\u20136.3 &#956;m<\/td><td>5\u201340 &#956;m<\/td><td>Not typically specified<\/td><td>ISO 1302, drawing callout<\/td><\/tr>\n    <tr><td>Pre-HIP satellite removal<\/td><td>No Ra target (satellite-cleared)<\/td><td>Baseline &#177;20%<\/td><td>Not specified<\/td><td>Process specification<\/td><\/tr>\n  <\/tbody>\n<\/table>\n<\/div>\n<p>For detailed measurement guidance on implant surfaces, see our guide on <a href=\"https:\/\/hlh-js.com\/resource\/blog\/abrasive-finishing-titanium-slm-orthopedic-implants-ra-targets-contamination-control-and-iso-13485\/\" target=\"_blank\" rel=\"noopener noreferrer\">abrasive finishing titanium SLM orthopedic implants<\/a>. For shot-peened aerospace component measurement, see <a href=\"https:\/\/hlh-js.com\/resource\/blog\/shot-peening-titanium-slm-aerospace-parts-ams-2430-fatigue-life-improvement-and-nadcap-compliance\/\" target=\"_blank\" rel=\"noopener noreferrer\">shot peening titanium SLM aerospace parts<\/a>.<\/p>\n\n<h2 id=\"sec-faq\">Frequently Asked Questions<\/h2>\n<div class=\"c-faq\">\n  <div class=\"c-faq-item\">\n    <input type=\"checkbox\" id=\"faq11a\" class=\"c-faq-chk\">\n    <label class=\"c-faq-q\" for=\"faq11a\">Should I measure Ra before and after each blast pass, or only at the end?<span class=\"c-faq-ic\">+<\/span><\/label>\n    <div class=\"c-faq-a\"><p>For production runs of qualified parts, Ra measurement after the final stage is sufficient if the process is validated and all parameters are controlled within the validated limits. For first-article runs, measure after each blast stage to build the Ra-reduction curve for the specific part and process \u2014 this data becomes the validation evidence and tells you exactly which stage achieves the specification. Measure after Stage 1 (coarse roughness normalization) to confirm the Stage 1 target is met before committing to Stage 2, and measure after Stage 2 to confirm whether Stage 3 (precision finish) is needed. In-process measurement prevents both over-blasting (if Stage 2 already meets the final specification) and under-blasting (if Ra after Stage 2 is above target).<\/p><\/div>\n  <\/div>\n  <div class=\"c-faq-item\">\n    <input type=\"checkbox\" id=\"faq11b\" class=\"c-faq-chk\">\n    <label class=\"c-faq-q\" for=\"faq11b\">What measurement instrument is recommended for titanium SLM lattice structures?<span class=\"c-faq-ic\">+<\/span><\/label>\n    <div class=\"c-faq-a\"><p>Contact profilometers cannot access internal lattice strut surfaces and cannot measure strut curvature accurately. For external lattice surfaces with cell openings above 500 \u03bcm, optical CSI at low magnification (5\u201310\u00d7 objective, field of view 1\u20132 mm) can characterize accessible strut surfaces when positioned correctly. For fully internal lattice surfaces that cannot be optically accessed, representative characterization requires: (1) sectioning a sacrificial coupon of the same build and measuring cross-section surface topography by contact or optical profilometry, or (2) replicating the internal surface with low-viscosity epoxy (replica method) and measuring the cured replica surface. Method (1) is more commonly used in production qualification of implant lattice structures.<\/p><\/div>\n  <\/div>\n  <div class=\"c-faq-item\">\n    <input type=\"checkbox\" id=\"faq11c\" class=\"c-faq-chk\">\n    <label class=\"c-faq-q\" for=\"faq11c\">How do I set the cut-off wavelength for measuring blasted titanium SLM surfaces?<span class=\"c-faq-ic\">+<\/span><\/label>\n    <div class=\"c-faq-a\"><p>Per ISO 4288: Ra 0.1\u20132 \u03bcm \u2192 \u03bbc = 0.8 mm (assessment length 4.0 mm); Ra 2\u201310 \u03bcm \u2192 \u03bbc = 2.5 mm (assessment length 12.5 mm). For blasted titanium SLM in the Ra 1\u20135 \u03bcm range, use \u03bbc = 0.8 mm as the primary choice. A practical check: if the Ra value changes by more than 20% when you switch from \u03bbc = 0.8 mm to 2.5 mm, the surface has significant mid-range wavelength content (residual staircase periodicity or waviness from the SLM scan pattern) that is being filtered differently. Report the \u03bbc value alongside Ra in all measurement records so results are comparable between instruments and operators.<\/p><\/div>\n  <\/div>\n  <div class=\"c-faq-item\">\n    <input type=\"checkbox\" id=\"faq11d\" class=\"c-faq-chk\">\n    <label class=\"c-faq-q\" for=\"faq11d\">Can I use the same Ra specification for medical and aerospace titanium SLM parts?<span class=\"c-faq-ic\">+<\/span><\/label>\n    <div class=\"c-faq-a\"><p>Not without application-specific review. Medical implant surfaces target Ra 1.0\u20133.0 \u03bcm for osseointegration \u2014 this range is biologically optimized for bone cell response and is not derived from any mechanical performance requirement. Aerospace structural surfaces target Ra 1.6\u20133.2 \u03bcm after shot peening, which reflects the peening process outcome, not a mechanical optimum per se. PVD coating substrates need Ra 0.4\u20131.6 \u03bcm for adhesion reasons. These specifications overlap in the Ra 1.6\u20133.0 \u03bcm range, but the meaning and the measurement protocol (which parameters, which instrument, which locations) differ between applications. Always derive the Ra specification from the engineering requirement for the specific application, not from a generic blasting specification.<\/p><\/div>\n  <\/div>\n<\/div>\n<div class=\"c-cta\">\n  <h2>Need Specialist Abrasive Media for Titanium SLM Finishing?<\/h2>\n  <p>Jiangsu Henglihong Technology Co., Ltd. is available to discuss abrasive media specifications for achieving precise Ra targets across the titanium SLM application spectrum. Contact our technical team for media grade recommendations tied to your specific Ra and Rz requirements.<\/p>\n  <a class=\"c-cta-btn\" href=\"https:\/\/hlh-js.com\/contact\/\" target=\"_blank\" rel=\"noopener noreferrer\">Contact Our Technical Team<\/a>\n<\/div>\n<\/div>","protected":false},"excerpt":{"rendered":"<p>&#8592; Complete Guide: Abrasive Finishing for Titanium SLM Parts Surface  [&#8230;]<\/p>","protected":false},"author":1,"featured_media":13999,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[62,175,138],"tags":[],"class_list":["post-13976","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-blog","category-industry","category-resource"],"_links":{"self":[{"href":"https:\/\/hlh-js.com\/zh\/wp-json\/wp\/v2\/posts\/13976","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/hlh-js.com\/zh\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/hlh-js.com\/zh\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/hlh-js.com\/zh\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/hlh-js.com\/zh\/wp-json\/wp\/v2\/comments?post=13976"}],"version-history":[{"count":2,"href":"https:\/\/hlh-js.com\/zh\/wp-json\/wp\/v2\/posts\/13976\/revisions"}],"predecessor-version":[{"id":13978,"href":"https:\/\/hlh-js.com\/zh\/wp-json\/wp\/v2\/posts\/13976\/revisions\/13978"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/hlh-js.com\/zh\/wp-json\/wp\/v2\/media\/13999"}],"wp:attachment":[{"href":"https:\/\/hlh-js.com\/zh\/wp-json\/wp\/v2\/media?parent=13976"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/hlh-js.com\/zh\/wp-json\/wp\/v2\/categories?post=13976"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/hlh-js.com\/zh\/wp-json\/wp\/v2\/tags?post=13976"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}