tim3130
2020-06-21T05:39:30+00:00
看了个小视频，把一块正方体的铁，锻造成轮毂，评论区有人问，铁的密度变了没？两个高赞，一方说变一方没变。我个人觉得没变[s:a2:偷吃][img]https://img.nga.178.com/attachments/mon_202006/29/-7Q5-awp2ZcT1kShs-12i.jpg.medium.jpg[/img][img]https://img.nga.178.com/attachments/mon_202006/29/-7Q5-bdh4ZbT1kShs-12i.jpg.medium.jpg[/img][img]https://img.nga.178.com/attachments/mon_202006/29/-7Q5-7ucuZcT1kShs-12i.jpg.medium.jpg[/img]