1000.

Iron sheets will deform when burned at high temperatures. As long as the temperature reaches 1000 degrees or above, they will deform. However, it also depends on the thickness and length of the iron sheet. Generally speaking, metal will deform when the temperature reaches the melting temperature. When the iron sheet is fixed, it will deform as long as the temperature reaches about 200 degrees, mainly due to the principle of thermal expansion and contraction.

Automatic tripping is based on the different expansion coefficients of iron sheets and copper sheets under the same temperature environment to cause bending, that is, deformation.