Aging treatment is an important heat treatment process widely used in the processing of metal materials, especially in the strengthening treatment of aluminum alloys, titanium alloys, and certain steels. The purpose is to improve the strength, hardness, and dimensional stability of the material by controlling the microstructure changes within the material. The aging furnace, as the key equipment for achieving aging treatment, has a direct impact on the final treatment effect due to the setting of aging time. Then, how can the aging time be scientifically and reasonably determined?



Firstly, the determination of aging time needs to take into account the type and composition of the material. Different materials have different mechanisms and speeds of precipitation phase formation during aging, so the required aging time is also different. For example, the 7xxx series aluminum alloys (such as 7075) require aging for 8 to 24 hours at 120℃, and the specific time needs to be adjusted according to the alloy composition and performance requirements. Some high-temperature alloys may require longer aging treatment to complete sufficient phase transformation.



Secondly, aging temperature is closely related to time, usually following the rule of 'the higher the temperature, the shorter the required time'. In actual production, the aging curve of the material (Time-Temperature-Property curve) is usually referred to, which reflects the trend of changes in the mechanical properties of the material at different temperatures and times. Through this curve, the aging time to achieve the target performance (such as optimal hardness or tensile strength) can be found.



In addition, the shape and size of the workpiece are also important factors affecting the aging time. Large or thick-walled workpieces, due to slower heat conduction, often require a longer holding time to ensure uniform and consistent overall temperature, avoiding the impact on overall performance due to incomplete aging in local areas. Generally, the standard of keeping warm for 1 hour per 25mm thickness can be used for estimation, and adjustments can be made in combination with actual detection.



Process requirements and performance objectives are also factors that cannot be ignored in determining the aging time. If the main goal is to increase the hardness and strength of the material, a longer aging time may be chosen to promote the complete precipitation of the precipitated phases; while in situations where a certain toughness needs to be maintained, the aging time may be appropriately shortened to prevent overaging and brittleness.



Finally, experimental verification and data analysis are indispensable links in determining the aging time. By testing the mechanical properties (such as hardness tests, tensile tests, etc.) of small batch samples after aging treatment at different times, the most suitable aging time can be optimized to ensure the stability and consistency of mass production.



In summary, the determination of aging time in the aging furnace is a process involving the comprehensive effect of multiple factors, which requires scientific setting based on material properties, process parameters, workpiece dimensions, and performance requirements, among other aspects. Only by fully understanding the behavior of materials and the principles of the process can the optimal effect of aging treatment be achieved, thereby improving the quality and reliability of products.