ISO 148-1 is an international test method for Charpy pendulum impact testing of metallic materials, used to measure the energy absorbed when a notched specimen fractures under a single high-rate impact.
This standard is commonly specified for material qualification, process verification, and quality control where impact toughness is a requirement. If you need help aligning your test setup to the edition cited on a customer drawing or purchase specification, contact our team.
ISO 148-1: Metallic materials — Charpy pendulum impact test — Part 1: Test method
ISO 148-1 defines the core Charpy pendulum impact test method for metallic materials using standardized notched test pieces (commonly V-notch and U-notch configurations). The output is the absorbed impact energy measured by a pendulum impact machine.
ISO 148-1 focuses on the conventional (non-instrumented) Charpy method. When instrumented impact measurements are required, a different standard is typically cited.
Quick Definition
What it is: A standardized Charpy pendulum impact test method for metallic materials.
What it measures: Energy absorbed by a notched specimen during fracture under a single pendulum strike.
Common outcome: Comparable impact energy results for material acceptance, comparison, or trend monitoring when specimen geometry, temperature, and machine verification are controlled.
What This Standard Covers
ISO 148-1 is centered on how to perform the Charpy pendulum impact test and report absorbed energy results for metallic materials.
In practical terms, it typically drives: specimen notch type selection (V or U), impact temperature requirements, and the need for a properly configured Charpy impact machine and fixtures to produce comparable absorbed-energy values.
Why This Standard Matters in Testing
Charpy impact energy is widely used as an indicator of impact toughness and sensitivity to brittle fracture under rapid loading, especially when comparing heats, product forms, weld procedures, or heat treatments.
Because Charpy results can be sensitive to temperature, notch quality, and machine condition, ISO 148-1 is often used alongside machine verification requirements to support defensible QC data and repeatable lab-to-lab comparisons.
Common Materials, Product Types, or Applications Covered
ISO 148-1 is used for metallic materials where impact performance is specified or monitored, such as steels and other structural alloys.
Common applications: mill qualification and receiving inspection, product certification testing, weld procedure qualification support, heat-treatment validation, and fracture-sensitivity screening across temperature.
Common Test or Verification Workflow
Most ISO 148-1 programs follow a controlled workflow that keeps specimen geometry, temperature, and machine performance aligned with the cited standard.
Common workflows: (1) prepare or source notched specimens, (2) condition specimens to the specified test temperature, (3) perform Charpy pendulum impact tests and record absorbed energy, (4) apply routine machine checks and periodic verification practices as required by the governing quality system and the cited standard set.
Equipment Commonly Used for This Standard
ISO 148-1 typically points labs toward a conventional Charpy pendulum impact testing system with fixtures and tooling suitable for the required notch type and energy range.
Common equipment: Charpy pendulum impact tester (appropriate energy capacity), striker(s) and supports/anvils compatible with the specified configuration, specimen centering/positioning tools, and safety guarding.
Common supporting tools: notch preparation equipment (or qualified notching services), dimensional inspection tools for specimen verification, and temperature-conditioning equipment (environmental chamber, cooling/heating bath, or equivalent) when testing at non-ambient temperatures.
If you are selecting a Charpy system (capacity, striker options, verification approach, and temperature-conditioning accessories), you can request a detailed quote for a configuration matched to your material range and throughput.
How to Read This Designation or Revision
ISO 148 is a multi-part standard series for Charpy pendulum impact testing of metallic materials.
ISO 148-1 identifies Part 1, which is the test method. The year (for example, “:2016”) identifies the edition being cited, and test setup and reporting expectations can depend on the specific edition referenced in a contract or governing specification.
Related Standards, Methods, or Frameworks
Many labs use ISO 148-1 together with complementary references that address machine verification and advanced (instrumented) impact measurements.
-
ISO 148-2: Verification of Charpy pendulum impact testing machines.
-
ISO 148-3: Reference test pieces used for indirect verification activities tied to machine verification practices.
-
ISO 14556: Instrumented Charpy V-notch impact testing (used when force/time or fracture-behavior data beyond absorbed energy is required).
Talk with us about ISO 148-1 testing equipment
If you’re updating a Charpy lab, expanding temperature capability, or aligning your system to a specific ISO 148-1 edition cited by a customer, talk with our team about machine configuration, accessories, and verification-ready setup details.