ASTM B177
Standard Guide for Engineering Chromium Electroplating
Provides guidance for depositing functional hard chromium while preserving required substrate and deposit properties.
What ASTM B177 specifies
ASTM B177 is a process guide for engineering or hard chromium rather than a conformance specification with universal classes. It covers substrate preparation, racking and anodes, cleaning, etching, chromium deposition, stress relief, post-plate hydrogen relief, grinding, honing, lapping, repair, and thickness, hardness, and adhesion testing. The required thickness and final size must come from the drawing. For a formal ferrous-substrate coating classification, ASTM B650 supplies Class 1 at 2.5–25 µm and Class 2 above 25 µm. Buyers should therefore avoid a bare B177 note and add thickness, finish size, significant surfaces, grinding allowance, and bake requirements.
Tests and the drawing call-out
Tests the document imposes
- Coating thickness
- Hardness
- Adhesion
- Surface finish and final dimensions
- Stress-relief and post-plate bake records
How to cite it
Drawing call-out
ENGINEERING CHROMIUM PLATE USING ASTM B177 GUIDANCE, <THICKNESS>, FINISH TO <SIZE AND ROUGHNESS>, <BAKE>Angle brackets mark the choices the drawing must make; every finish page shows a completed example.
Finishes specified to ASTM B177
ASTM B177 — frequently asked
Does ASTM B177 specify a hard-chrome thickness?
No. It is guidance rather than a thickness-class specification. The drawing must state deposit thickness and final dimensions.
Which ASTM document classifies hard chrome on steel?
ASTM B650 is the companion specification for ferrous substrates. It defines Class 1 as 2.5–25 µm and Class 2 as greater than 25 µm.
Why state grinding allowance?
Hard chromium used for buildup is commonly deposited oversize and ground or honed to final dimensions. The plater needs both as-plated allowance and finished size.
ASTM B177 is copyrighted by ASTM International. This page explains the document so a drawing can be read; it does not reproduce the standard. Purchase the current edition from the publisher. Official source ↗