????y????????????????????????????????????14???????????????3D??????????????ù????????????μ????????????????????????
?????????????????????????????????Arcam AB??1?SLM Solutions Group AG??????3D?????????????????????????????????????????????????Rolls-Royce Holdings PLC????????????????????United Technologies Corp.?????????????????
Arcam?????SLM Solutions??????????????3D??????????????????????????????е?????????????????????????CEO???·??÷?????Jeff Immelt?????3D???????“??????????????????????????????????”