When the nuclear sound skeleton is old, we can use some professional words to describe its old degree. For example, "obsolescence" can be used to describe the aging problem of materials after long-term use, and "aging deterioration" can also be used to describe the situation that materials gradually lose their original properties. In addition, "aging fatigue" can be used to describe the fatigue phenomenon of materials after long-term use, and "old corrosion" can also be used to describe the corrosion phenomenon of materials under the action of environmental factors such as chemistry and physics. To sum up, by using some technical terms, we can describe the old nuclear acoustic skeleton more accurately.