Why do magnetic stirrers with heating function choose aluminum plates

Stainless steel is the easiest to deform because stainless steel has the worst thermal conductivity of the three. When we are heating stainless steel, because of its slow heat transfer rate, the first heated part will first produce thermal expansion, and the adjacent area will not have too much thermal expansion because of its slow heat transfer and can not get the same heat in time, so that the material in the previous thermal expansion area has no place to extend and arch up and down, thereby driving the deformation and distortion of the whole material. The thermal conductivity of aluminum is better, and the deformation phenomenon will not occur.