How to improve the mechanical properties of materials

Metal material: 1. Microscopically, cold deformation and work hardening can be carried out to improve the strength and reduce the plasticity of materials. 2. flour and rice can improve both; 3. Adding alloying elements can also improve the mechanical properties (scholars are doing it); 4, the plate can strengthen the ribs to improve the strength; Nonmetals: I don't know much about it. Composite materials may be a solution. What materials and shapes do you specify?