ASTM A108-24
Standard Specification for Steel Bar, Carbon and Alloy, Cold-Finished

Standard No.

ASTM A108-24

Release Date

2024

Published By

American Society for Testing and Materials (ASTM)  US  /  ASTM

Latest

ASTM A108-24

Introduction

Analysis of the Standard's Core Content

ASTM A108 specifies the technical requirements for cold-finished carbon and alloy steel bars in straight and coiled form, suitable for heat treatment, machining, or direct use. The standard identifies material grades by chemical composition or steel number and defines three progressive tolerance grades.

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Comparison of Material Manufacturing Processes

Process Type	Round Bar Processing Method	Square/Hexagonal Bar Processing Method	Applicable Carbon Content Range
Cold Working	9 types including cold drawing/turning and polishing	Cold Drawing/Cold Rolling	≤0.55%(Carbon Steel) ≤0.38%(Alloy Steel)
Heat Treatment	5 combinations including annealing/normalizing/quenching and tempering		＞0.55%(Carbon Steel) ＞0.38%(Alloy Steel)

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Key Tolerance Parameters

Round Bar Size Tolerance Example: When the carbon content is ≤0.28%, the Level 1 tolerance for a 1.5-inch (38.1mm) cold-drawn round bar is 0.002 inches (0.051mm), while the tolerance for a Level 3 ground and polished product of the same size can reach 0.0008 inches (0.0203mm).

Surface Roughness Requirements: Ra ≤ 60μin for Level 2 turned and polished parts, and Ra ≤ 20μin for Level 3 ground and polished parts.

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Implementation and Application Recommendations

1. Material Selection: Level 3 tolerance grinding and polishing are recommended for high-precision parts.
2. Anti-corrosion Treatment: Anti-rust oil must be applied before transportation, and surface cleanliness testing is recommended before precision machining.
3. Supplementary Requirements: Special applications such as military applications may activate supplementary clauses S1-S8, requiring traceability information such as the melting process.

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Technology Evolution Analysis

Major updates to the 2024 version include: 1) Clarification of WTO/TBT international standard-setting principles; 2) Addition of continuous casting process reporting requirements (S4); and 3) Refinement of the surface defect tolerance grading for sulfur-containing steels. Compared to the A29/A29M hot-rolled standards, the dimensional accuracy of cold-finished products is improved by 50-300%.

ASTM A108-24 Referenced Document

• ASTM A29/A29M Standard Specification for Steel Bars, Carbon and Alloy, Hot-Wrought and Cold-Finished, General Requirements for
• ASTM A304 Standard Specification for Carbon and Alloy Steel Bars Subject to End-Quench Hardenability Requirements
• ASTM A322 Standard Specification for Steel Bars, Alloy, Standard Grades
• ASTM A370 Standard Test Methods and Definitions for Mechanical Testing of Steel Products
• ASTM A400 Standard Practice for Steel Bars, Selection Guide, Composition, and Mechanical Properties
• ASTM A510/A510M Standard Specification for General Requirements for Wire Rods and Coarse Round Wire, Carbon Steel, and Alloy Steel*， 2025-05-01 Update
• ASTM A576 Standard Specification for Steel Bars, Carbon, Hot-Wrought, Special Quality

ASTM A108-24 history

• 2024 ASTM A108-24 Standard Specification for Steel Bar, Carbon and Alloy, Cold-Finished
• 2018 ASTM A108-18 Standard Specification for Steel Bar, Carbon and Alloy, Cold-Finished
• 2013 ASTM A108-13 Standard Specification for Steel Bar, Carbon and Alloy, Cold-Finished
• 2007 ASTM A108-07 Standard Specification for Steel Bar, Carbon and Alloy, Cold-Finished
• 2003 ASTM A108-03e1 Standard Specification for Steel Bar, Carbon and Alloy, Cold-Finished
• 2003 ASTM A108-03 Standard Specification for Steel Bar, Carbon and Alloy, Cold-Finished
• 1999 ASTM A108-99 Standard Specification for Steel Bars, Carbon, Cold-Finished, Standard Quality
• 1995 ASTM A108-95 Standard Specification for Steel Bars, Carbon, Cold-Finished, Standard Quality
• 0000 ASTM A108-93(1995)e1

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