Metals
If the curvature and chamfering are insufficient when forming a part, stress will be generated locally there, resulting in failures. Multifaceted evaluations of strength characteristics and product shapes make it easier to identify the causes of failures.
In creating cast metal and cast iron parts, when the molten metal flows into the mold, the cast metal sometimes cools and hardens with the bubbles that arose inside the molten metal intact. The bubbles in the cast metal have poor mechanical characteristics in comparison with other regions, and so will cause failures. With welding, if the crystal structure of the welding metal is non-uniform, when strain is applied to the welded parts due to heat or external forces, stress will concentrate on the non-uniform parts, leading to failures. The interior structure of the metal has an impact on its strength and durability. Multifaceted evaluations of strength characteristics and the internal structure make it easier to identify the causes of failures.
When products are repeatedly used over long periods, if there is even a tiny amount of damage, that damage can dramatically reduce operating life. Force is concentrated with respect to the irregular surface of the damage. Products then fail due to strain produced at the damaged part. Multifaceted evaluations of strength characteristics and observations of damaged surfaces make it easier to identify the causes of failures.
The crystal structure of a metal changes depending on the temperature applied to the metal. The crystal structure inside the metal is controlled by controlling the applied temperature and the cooling time. Techniques for controlling hardness and strength have been utilized in a variety of contexts, from ancient swordsmiths to current cutting edge metal processing. Multifaceted evaluations of strength, the composition of metal crystals, and crystalline structures enable the reliable selection of materials, and the identification of the causes of failures.
