Steel and aluminum alloys have high thermal expansion coefficients, where even tiny temperature fluctuations can cause deformations of tens to hundreds of nanometers.
High-quality Jinan blue granite has an extremely low thermal expansion coefficient, maintaining near-constant temperature dimensional stability.
Key point: It is not enough for the overall environment to be constant temperature; one must also rely on the base material to suppress local temperature difference deformations.
Continuous heating from motor coils generates local hotspots. If the base has uniform heat conduction and low expansion, it can significantly alleviate thermal warping; if the base material is poor, local heating causes bending, the guide rail reference tilts accordingly, and the bidirectional positioning error continues to expand.<\/li>\n\n\n\n
External factory vibrations, motor start-stop disturbances, and cable drag forces all excite micro-vibrations in the platform.
Insufficient stiffness: The base bends slightly under loads and clamping forces, causing the motion trajectory to pitch and yaw;
Insufficient damping: Vibration decay is slow, resulting in long-lasting micro-vibrations after motion stops, making it impossible to achieve instantaneous stable positioning.
Granite has high density and internal damping far superior to cast iron and aluminum, allowing it to quickly dissipate vibration energy and avoid resonance, making it the preferred substrate for nanometer platforms.<\/li>\n\n\n\n
Metal components continuously release internal stress, deforming slowly over months.
Granite components that have undergone natural aging constant temperature artificial aging, and precision grinding, have basically completed stress release, allowing their geometric shape to be maintained long-term.
For semiconductor inspection and micro-assembly equipment that require continuous year-round mass production, long-term accuracy retention is far more important than single-point accuracy at the time of factory delivery.<\/li>\n<\/ol>\n\n\n\n
- \n
- Geometric Integrity of the Integrated Base
High-end nano-motion platforms generally adopt an integrated granite base, where the guide rail mounting surface, grating reference surface, and load working surface are ground into a single piece at once.
This reduces splicing and assembly interfaces, minimizing the cumulative geometric errors caused by multi-layer assembly.
Even if top-tier linear motors are used, if the base consists of multiple spliced components or the reference surfaces are machined separately, inherent defects in flatness and straightness will exist that cannot be corrected during subsequent commissioning.
III. Intuitive Analogy for Easier Understanding
Compare the nano-motion platform to a high-precision vernier caliper:
\u2705 Linear motor Servo = Sliding vernier scale, responsible for precise movement;
\u2705 Granite base = Main scale of the caliper (the reference body).
If the main scale itself is bent, thermally deformed, or constantly vibrating, no matter how high the accuracy of the vernier scale is, the measurement results will still be continuously distorted.
Once the reference wobbles or deforms, all closed-loop compensation algorithms are merely “treating the symptoms.”
IV. Real-world Industry Pain Points
Many equipment manufacturers equip their machines with top-tier linear motors and nano-gratings, pass the accuracy commissioning, and deliver to customers, only to experience accuracy drift after 1 to 3 months of operation. Troubleshooting the servo, encoder, and guide rails yields no faults; the root cause is often:
Insufficient base material grade, inadequate aging, substandard grinding of the reference surface, or weak structural stiffness, causing continuous reference deformation due to temperature changes and stress.<\/li>\n<\/ol>\n\n\n\n![\"\"](\"https:\/\/jtlcnc.com\/wp-content\/uploads\/2026\/08\/3.png\")
<\/figure>","protected":false},"excerpt":{"rendered":"Nanometer-level positioning accuracy: The drive determines the upper limit, while the base secures the bottom line.When positioning indicators enter the nanometer scale, many people fall into a cognitive trap: wanting to achieve nanometer-level motion by blindly pursuing high-end linear motors, ultra-high resolution gratings, and advanced servo algorithms. However, extensive field verification in semiconductor inspection, optical…<\/p>","protected":false},"author":1,"featured_media":3215,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_seopress_titles_title":"","_seopress_titles_desc":"","_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":"","_kad_blocks_custom_css":"","_kad_blocks_head_custom_js":"","_kad_blocks_body_custom_js":"","_kad_blocks_footer_custom_js":"","_kadence_starter_templates_imported_post":false,"_kad_post_transparent":"","_kad_post_title":"","_kad_post_layout":"","_kad_post_sidebar_id":"","_kad_post_content_style":"","_kad_post_vertical_padding":"","_kad_post_feature":"","_kad_post_feature_position":"","_kad_post_header":false,"_kad_post_footer":false,"_kad_post_classname":"","footnotes":""},"categories":[35],"tags":[],"class_list":["post-3214","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-news"],"taxonomy_info":{"category":[{"value":35,"label":"NEWS"}]},"featured_image_src_large":["https:\/\/jtlcnc.com\/wp-content\/uploads\/2026\/08\/3.png",473,791,false],"author_info":{"display_name":"jinxing6611@gmail.com","author_link":"https:\/\/jtlcnc.com\/fr\/author\/jtlcnc\/"},"comment_info":0,"category_info":[{"term_id":35,"name":"NEWS","slug":"news","term_group":0,"term_taxonomy_id":35,"taxonomy":"category","description":"","parent":0,"count":362,"filter":"raw","cat_ID":35,"category_count":362,"category_description":"","cat_name":"NEWS","category_nicename":"news","category_parent":0}],"tag_info":false,"_links":{"self":[{"href":"https:\/\/jtlcnc.com\/fr\/wp-json\/wp\/v2\/posts\/3214","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/jtlcnc.com\/fr\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/jtlcnc.com\/fr\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/jtlcnc.com\/fr\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/jtlcnc.com\/fr\/wp-json\/wp\/v2\/comments?post=3214"}],"version-history":[{"count":1,"href":"https:\/\/jtlcnc.com\/fr\/wp-json\/wp\/v2\/posts\/3214\/revisions"}],"predecessor-version":[{"id":3216,"href":"https:\/\/jtlcnc.com\/fr\/wp-json\/wp\/v2\/posts\/3214\/revisions\/3216"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/jtlcnc.com\/fr\/wp-json\/wp\/v2\/media\/3215"}],"wp:attachment":[{"href":"https:\/\/jtlcnc.com\/fr\/wp-json\/wp\/v2\/media?parent=3214"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/jtlcnc.com\/fr\/wp-json\/wp\/v2\/categories?post=3214"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/jtlcnc.com\/fr\/wp-json\/wp\/v2\/tags?post=3214"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}