When designing and evaluating the application of magnets, in addition to considering performance requirements, the most important thing is whether the magnet can exert its effectiveness in the actual environment and the duration of its ability to last. Environmental testing is a quality management program established for this purpose, which simulates the actual environment that magnets may face, observes changes in magnets, and enables magnets to truly meet the requirements and standards of actual operation.

Accelerated magnet aging test is one of the most commonly used environmental tests when detecting magnets. This series of experiments utilizes increased and controlled environmental conditions such as pressure, temperature, humidity, and contact with substances to enhance the potential environmental impact on magnets. In other words, we simulate the changes that magnets may undergo in actual environments over a long period of time by exposing them to extreme experimental environments. Accelerated aging testing can effectively shorten the detection time and to some extent ensure the effective operation of the magnet in a specific period and actual environment.

1. HAST - High Acceleration Temperature and Humidity Pressure Test

The full English name is High Accelerated Temperature and Humidity Stress Test, abbreviated as HAST, sometimes referred to as Unsaturated Steam Test. The purpose is to evaluate the resistance of the magnet itself to moisture, which is also highly correlated with its rust resistance.

This experiment sets the environmental conditions at higher temperatures, (unsaturated) humidity, and air pressure according to product requirements. By increasing the air pressure, moisture can quickly penetrate from the surface of the magnet into the interior. Therefore, the structure and surface density of the magnet become key factors affecting the results. Relevant information can refer to the conditions and standards established in document JEDEC22-A118.

The Low Weight Loss Test is a test derived from HAST. In response to the development of wind power generation, electric motors, and permanent magnet motors, the demand for uncoated magnets has increased, and tests to evaluate their corrosion resistance have also received increasing attention. The set test standards are commonly referred to as low weight loss magnets, and their environmental conditions and detection standards are as follows:

2. PCT - Pressure cooker cooking test/saturated steam test

The full English name is Pressure Cook Test, abbreviated as PCT. Its purpose is also to evaluate the moisture resistance and rust resistance of magnets, and to place the finished product in a heated, pressurized, and saturated humidity environment to accelerate its corrosion effect. The tolerance of the magnet coating is the focus of the test.

Unlike HAST under unsaturated humidity conditions, its environmental conditions are set at saturated humidity, 120 degrees Celsius, 2 atmospheric pressure, and the test time is accumulated in 24 hours as the minimum time unit. Relevant information can refer to the conditions and standards established in the JESD22-A102-C document.