There are many reasons for insufficient hardness, such as over-aging, or insufficient bar temperature before extrusion, insufficient aging time and aging temperature, and it is also related to the thickness of the profile. What is your aging temperature? How long is it? Generally, the heating time is two to three hours, the temperature is between 190-220, and the heat preservation is two to four hours. If the hardness is higher, the temperature should be maintained for at least five hours.