ISO 25178-601:2010

Overview

ISO 25178-601:2010 specifies the metrological (nominal) characteristics of contact (stylus) areal surface texture measuring instruments. It is part of the ISO 25178 series for GPS - Surface texture: Areal and describes how stylus-based areal profilers should be characterised for reliable measurement of surface texture. The standard defines terminology, measurement-loop concepts, instrument response behaviour and the key performance parameters that influence measurement uncertainty.

Key topics and technical requirements

• Scope and terms - Definitions for coordinate system, measurement loop, user adjustment and residual correction error, aligned with ISO 3274, ISO 4287 and VIM.
• Lateral scanning system - Role of the areal reference guide and the X/Y drive units; requirements for lateral position sensors and scanning trajectory.
• Probing system components - Characterisation of the stylus, pivot, probe (transducer), digitizing system and associated errors (e.g., arcuate motion caused by stylus rotation).
• Metrological characteristics - Formal definitions and measurement considerations for:
  • Measuring volume
  • Response curve and amplification coefficients (linearization of instrument response)
  • Instrument noise (internal/electronic), static and dynamic noise
  • Sampling intervals in X and Y (Dx, Dy) and digitization step in Z (Dz)
  • Lateral resolution and width limit for full height transmission
  • Maximum local slope, speed of measurement, probing dynamics and critical dynamic
• Measurement uncertainty influences - Summary of typical metrological characteristics (tabulated in the standard) that affect uncertainty, and guidance on adapting filters and sampling to avoid degrading resolution or transmission.
• Annexes - Classification of instrument configurations (Annex A), instrument features (Annex B) and relationship to the GPS matrix model (Annex C).

Practical applications and intended users

ISO 25178-601 is intended for:

• Metrology and calibration laboratories establishing acceptance, verification or calibration routines for stylus areal profilers.
• Instrument manufacturers designing or specifying contact (stylus) areal surface texture measuring instruments.
• Quality assurance and R&D teams in manufacturing sectors (precision engineering, automotive, aerospace, medical devices) that specify surface texture requirements or validate measurement systems.
• Standards authors and procurement specialists who need clear, standardised metrological characteristics for contractual or compliance purposes.

The standard helps ensure consistent, traceable areal surface texture measurement practice using stylus instruments and supports correct interpretation of parameters such as lateral resolution, sampling intervals and instrument noise.

Related standards

• ISO 25178 series (Parts 2, 3, 6, 7, 602–605)
• ISO 3274:1996 (profile method - nominal characteristics of stylus instruments)
• ISO 4287 (terms and parameters for profile)
• ISO 10360-1 and ISO/IEC Guide 99 (VIM)