ASTM A108
ASTM A108 is the Standard Specification for Steel Bar, Carbon and Alloy, Cold-Finished. It covers cold-drawn, turned and polished, or turned, ground, and polished carbon and alloy steel bars in rounds, squares, and hexagons. Cold finishing provides improved surface finish, tighter dimensional tolerances, and higher yield strength than hot-rolled bar of the same chemistry.
ASTM A108 covers a wide range of grades from low carbon (1018) through medium carbon (1045) to alloy grades (4140, 4150, 8620), making it the standard specification for precision-machined components in aerospace, defense, and industrial programs.
ASTM A 108 grades range from UNS G10180 (1018) through alloy grades. Cold finishing increases yield strength 10–20% above hot-rolled, with surface roughness Ra 63–125 µin for cold-drawn, and Ra 32–63 µin for turned and ground. Tolerances per ASTM A 108 Table 1 for rounds (h9 or h11 class) depending on finish specified.
- Precision Machined Aerospace Components
- Shafts, Spindles, and Pins
- Hydraulic Actuator Components
- Fastener Blanks and Tooling
- Defense and Industrial Precision Parts
Alloy Steel Bar
ASTM standard specifications for hot-wrought and cold-finished alloy steel bars for aerospace and defense applications.
Alloy Steel Overview
Alloy steel material grades and specifications for aerospace structural, landing gear, and defense applications.
Certified Material for Critical Service
ASTM A108 material is supplied with full mill certifications confirming grade, chemical composition, mechanical properties (if required), cold finish condition, and complete heat-lot traceability per ASTM A108.