ISO 898-1:2013

Overview

ISO 898-1:2013 - Mechanical properties of fasteners made of carbon steel and alloy steel - Part 1 covers the mechanical and physical properties of bolts, screws and studs (fasteners) with specified property classes, for both coarse thread and fine pitch thread. The standard applies to metric fasteners tested at an ambient temperature range of 10 °C to 35 °C, and defines how to evaluate finished fasteners made from carbon or alloy steels with ISO metric threads.

Key scope points:

• Applies to threaded fasteners with ISO metric triangular threads (coarse M1.6–M39, fine M8×1–M39×3).
• Specifies property classes, required tests, and marking for bolts, screws and studs.
• Excludes set screws (see ISO 898-5) and does not set requirements for weldability, corrosion resistance, shear resistance, torque/clamp-force performance or fatigue resistance.

Key Topics and Requirements

ISO 898-1:2013 addresses the following technical topics and test requirements:

• Designation system for property classes (strength grades for bolts, screws and studs).
• Mechanical tests: tensile strength, elongation, proof load, torsional test and wedge-loading tensile tests for finished fasteners.
• Physical and material checks: hardness testing, decarburization and carburization assessment, retempering, and head soundness inspection.
• Applicability and limitations: criteria for reduced loadability (e.g., low or countersunk heads), full-size vs. waisted shanks, and testing at ambient conditions.
• Test methods and sampling: guidelines for manufacturer, supplier and purchaser testing, and machining test pieces from parts.
• Marking and identification: manufacturer marks and property-class marking for traceability and compliance.
• Informative annexes covering relationship between tensile strength and elongation and effects of elevated temperatures on fastener properties.

Practical Applications and Who Uses This Standard

ISO 898-1 is essential for:

• Fastener manufacturers and heat-treatment shops specifying property classes and production tests.
• Design and mechanical engineers selecting fasteners for bolted joints.
• Quality inspectors and procurement professionals verifying mechanical performance and marking.
• Standards committees and technical spec writers creating product specifications for machinery, automotive, construction and industrial equipment.

Practical benefits:

• Ensures consistent tensile and proof-load performance across suppliers.
• Supports reliable selection of carbon and alloy steel fasteners for specified service conditions.
• Enables clear acceptance testing and traceability through standardized marking.

Related Standards

Relevant cross-references include: ISO 898-2, ISO 898-5, ISO 898-7, ISO 68-1, ISO 261 / ISO 262, ISO 965 (thread tolerances), ISO 6892-1 (tensile testing), and ISO standards for hardness and surface discontinuities (e.g., ISO 6506/6507/6508, ISO 6157). For torque/clamp-force testing see ISO 16047.

Keywords: ISO 898-1:2013, mechanical properties of fasteners, bolts screws studs, property classes, coarse thread, fine pitch thread, tensile strength, proof load, decarburization, metric fasteners.