void search()
{
    char key[TSIZE];
    printf("\n\t请输入搜索型号： ");   
    scanf("%s",key);
        
   
    int i=1;
    printf("\n\t序号　　名称　　   型号　　  大面　　 小面\n\n");
   
    current=head;
   
    while(current!=NULL)
            {
                             
           
            if(current->Model == key)
            {
                printf("\t%-7d %-10s %-10s %-8d %-4d\n",
                i,
                current->Name,
                current->Model,
                current->Width,
                current->yaxiandepth);
            }               
              
            
            current=current->next ;   
            i++;
            }
   
   
}

找出原因了，要用比较字符串函数，

void search()
{
    char key[TSIZE];
    printf("\n\t请输入搜索型号： ");   
    scanf("%s",key);
        
   
    int i=1;
    printf("\n\t序号　　名称　　   型号　　  大面　　 小面\n\n");
   
   
    int r;
     
   
    current=head;
   
    while(current!=NULL)
            {
                             
            r=strcmp(current->Model,key);
            if(!r)
            {
                printf("\t%-7d %-10s %-10s %-8d %-4d\n",
                i,
                current->Name,
                current->Model,
                current->Width,
                current->yaxiandepth);
            }               
              
            
            current=current->next ;   
            i++;
            }
   
   
}