ISO 10825-1:2022

Overview

ISO 10825-1:2022 - Gears - Wear and damage to gear teeth - Part 1: Nomenclature and characteristics defines a common vocabulary and descriptive criteria for the typical modes of gear tooth wear and damage. The standard classifies, identifies and describes the appearance and characteristics of the most common failure modes so users can consistently report and, in many cases, recognize changes from the original condition. It is based largely on experience with steel gears; many modes are relevant to other materials, but the document does not cover all failure types for plastics, bronze or powder‑metal gears. ISO 10825-1:2022 specifies terminology only - it does not prescribe causes, diagnostic procedures, or preventive measures, nor does it attempt to define “gear failure.”

Key topics and technical content

The document is organized to help inspect and describe gear tooth conditions, including:

• Classes and modes of failure: an overarching classification framework for damage types.
• Tribological damages (non‑fatigue): polishing wear (mild → severe), scratches, abrasive wear, scuffing (hot/cold, severity levels), adhesive wear, fretting corrosion and interference wear.
• Fatigue damage: contact fatigue (micropitting, macropitting, case crushing, white‑layer flaking, tooth flank fracture (TFF), tooth interior fatigue fracture (TIFF)) and bending fatigue (tooth‑root cracks and related fractures).
• Non‑fatigue fracture: brittle, ductile and semi‑brittle fracture descriptions; tooth root and shear fractures.
• Plastic deformation: indentation, brinelling, cold/hot flow, ridging, burrs and related deformations.
• Manufacturing issues and surface damage: forging/hardening/grinding cracks, grinding burn, case/core separation, corrosion, cavitation, erosion, electric discharge and overheating.
• Clear definitions and photographic/descriptive guidance (where applicable) to assist in identifying and reporting appearance and condition changes.

Practical applications

• Standardized failure reporting and inspection records for maintenance teams and reliability engineers.
• Common terminology for root cause analysis and communication between manufacturers, service providers and laboratories.
• Reference for preparing inspection protocols, condition‑monitoring reports and procurement specifications.
• Training material for maintenance, inspection and failure‑analysis personnel to recognize and describe common wear and damage phenomena.
• Useful in mechanical design reviews where clarifying expected damage modes improves specification of materials and treatments.

Who should use this standard

• Gear designers and OEMs, maintenance and reliability engineers, failure analysis specialists, tribologists, inspection and QA personnel, and standards committees involved with gear systems.

Related standards

• ISO 10825‑1 is part of the ISO gear standardization activity (ISO/TC 60). Users should consult other ISO gear standards and later parts of the ISO 10825 series for additional guidance, testing or measurement protocols.

Keywords: ISO 10825-1, gear wear, gear tooth damage, gear failure modes, gear inspection, contact fatigue, micropitting, macropitting, scuffing, abrasive wear, gear nomenclature.