jäähtymisprofiilia

Jäähtymisprofiili, or cooling profile, is the record of temperature change over time during the cooling of a material from an elevated state to a lower temperature. It is used primarily in metallurgy and heat‑treatment processes to characterize how quickly or slowly an alloy loses heat, which in turn influences its microstructure, mechanical properties, and residual stresses. The profile is obtained by embedding a thermocouple or other temperature sensor in the material or placing it in close proximity, then recording the temperature as the material is cooled, either naturally in ambient air, in a controlled furnace, or with forced convection or quenching media.

The shape of a cooling profile is described by key parameters such as the cooling rate, which may be expressed in degrees Celsius per hour or per minute, and the dwell times at various temperature ranges. For example, austenitic steels often require controlled cooling through the martensite transformation range to avoid brittleness. In casting, the cooling rate determines grain size and porosity. In forging, the cooling profile can influence decompression embrittlement. In heat‑treated metal alloys such as aluminum or titanium, the exposure to specific temperature windows during cooling can be critical for achieving desired hardness or tensile strength.

Modern laboratories use computerized data acquisition systems to generate cooling profiles with high temporal resolution. By comparing measured profiles against calibrated standards, engineers can validate process parameters, troubleshoot defects, and verify compliance with specifications. In additive manufacturing, where different layers are cooled at different rates, the overall cooling profile can be modelled to predict warping and residual stresses. Thus, jäähtymisprofiilia serves as a fundamental tool in material science, manufacturing engineering, and quality control.