ASTM E968-25 PDF
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St ASTM E968-25
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Ст ASTM E968-25
Original standard ASTM E968-25 in PDF full version. Additional info + preview on request
Full title and description
ASTM E968-25 — Standard Practice for Heat Flow Calibration of Differential Scanning Calorimeters. This practice provides procedures and recommendations to calibrate the heat‑flow axis of differential scanning calorimeters (DSCs) and quantitative differential thermal analyzers (DTAs) so that measured heats or enthalpies of transition and specific heat capacities are meaningful in an absolute sense.
Abstract
This concise practice describes the method for heat‑flow calibration of DSCs over a wide temperature range, including guidance on instruments, referenced units, and allowable computer/electronic data‑processing approaches. It is intended to enable reliable measurement of transition energies and specific heat capacities by providing a repeatable calibration procedure and related considerations for laboratory use.
General information
- Status: Active.
- Publication date: April 1, 2025.
- Publisher: ASTM International.
- ICS / categories: 17.200.10 (Heat; Calorimetry).
- Edition / version: E968-25.
- Number of pages: 5.
Scope
The practice covers heat‑flow calibration of differential scanning calorimeters over the temperature range from −130 °C to +800 °C. Values stated in SI units are to be regarded as standard. Computer or electronic instrument techniques and data‑manipulation procedures equivalent to the practice may be used. The standard also notes that users are responsible for adopting appropriate safety, health, and environmental practices prior to use.
Key topics and requirements
- Procedures for calibrating the heat‑flow axis of DSCs/DTAs to enable absolute enthalpy measurements.
- Applicable temperature range: −130 °C to +800 °C and use of SI units as the standard.
- Allowance for computer/electronic‑based instruments and equivalent data‑processing methods.
- Guidance on ensuring traceable and reproducible calibration for measurement of transition energies and specific heat capacities.
- Notes on user responsibility for safety and applicability of regulatory limitations when using the practice.
Typical use and users
Used in research and quality laboratories, instrument calibration facilities, and by DSC/DTA instrument manufacturers and service providers. Typical users include thermal analysis technicians, laboratory managers, R&D scientists, and anyone responsible for producing quantitative calorimetric enthalpy or specific‑heat data that require validated heat‑flow calibration.
Related standards
Closely related ASTM standards include E967 (temperature calibration of DSCs/DTAs) and test methods for enthalpy and melting/crystallization measurements (for example E793). Internationally, the ISO 11357 series (Differential Scanning Calorimetry) addresses related DSC principles and measurements and is commonly referenced alongside ASTM practices.
Keywords
differential scanning calorimetry, DSC, heat flow calibration, calorimetry, enthalpy, specific heat capacity, thermal analysis, DTA, instrument calibration, SI units.
FAQ
Q: What is this standard?
A: ASTM E968-25 is a Standard Practice that specifies how to calibrate the heat‑flow (enthalpy) response of differential scanning calorimeters and quantitative differential thermal analyzers so measured heats and specific‑heat data are quantitatively meaningful.
Q: What does it cover?
A: It covers heat‑flow calibration procedures over the temperature range −130 °C to +800 °C, use of SI units, allowance for computer/electronic data methods, and user responsibilities for safety and regulatory considerations.
Q: Who typically uses it?
A: Thermal analysis laboratories, instrument manufacturers and service organizations, R&D groups, and quality control labs that perform DSC/DTA measurements requiring quantitative enthalpy or specific‑heat results.
Q: Is it current or superseded?
A: E968-25 is the current (active) edition published in 2025 and supersedes the older E968-02(R2014) practice. (Older editions such as the E968‑02 revision were in circulation and referenced historically; users should adopt the E968‑25 text for current practice.)
Q: Is it part of a series?
A: E968 is part of the ASTM thermal‑analysis family of standards under Committee E37 and is often used alongside related standards such as E967 (temperature calibration), E793 (enthalpies of fusion), and international standards in the ISO 11357 DSC series.
Q: What are the key keywords?
A: Differential scanning calorimetry (DSC), heat‑flow calibration, enthalpy of transition, specific heat capacity, calorimetry, DSC calibration, thermal analysis.