Molybdenum alloy has high strength and hardness, poor toughness, brittleness, easy to break, and poor machinability. However, because of its high melting point, low density, and low coefficient of thermal expansion, it is often used to manufacture various high-temperature parts in aviation and aerospace. The two molybdenum parts are the scriú moluibdín and molybdenum bolt, as shown in the attached figure. The blank is hot rolled Ф 16mm molybdenum alloy steel bar. During processing, it is found that the material has a low density and very high skin hardness, which should be annealing residual hardness. Within the surface layer, the hardness is still very high, the toughness is poor, and the heat conduction is slow.
Tá sé an-deacair próiseáil a dhéanamh le gnáth-uirlisí cruach ardluais nó le huirlisí cairbíde cementáilte. Ar an gcéad dul síos, caitheann cliatháin tosaigh agus chúl agus leideanna an uirlis go tapa. Cuir sreabhach gearrtha leis agus bain úsáid as paraiméadair gearrtha éagsúla faoi ghnáthchoinníollacha le go leor tástálacha, nach féidir torthaí sásúla a fháil. Go ginearálta, mura bhfuil ach 4 phíosa lanna sorcóireacha ann, is gá iad a chur in ionad; Ar an dara dul síos, nuair a bhíonn an uirlis beagán caite, tá lochtanna ag titim slaig ar na codanna, agus tarlaíonn titim slaig nuair a bhíonn an deireadh árasán ag tabhairt aghaidh, ag gearradh agus ag snáithiú. Is féidir le meaisínithe an chiorcail lasmuigh agus an meaisínithe aghaidh deiridh na ceanglais líníochta a chomhlíonadh go bunúsach nuair a bhíonn an uirlis bailchríochnaithe fós géar, ach ní féidir titim slaig an mheaisínithe snáithe a sheachaint.
Sa phróiseáil iarbhír, an éifeacht casadh M6scriúnna moluibdínbocht, agus is minic go bhfuil an t-alt snáithe briste ón deireadh sa phróiseáil, rud nach féidir a sheachaint. Ní úsáidtear ach meaisínithe dísle scriúnna. Glacann M12 CNC ardluais-snáithe gearrthóir dúbailte ag casadh, agus tá an éifeacht an-oiriúnach. Mar gheall ar fhad fada an dá chuid, sa phróiseáil iarbhír, déantar an chéim casadh snáithe go ginearálta tar éis fad iomlán eitleán gearrtha an chiorcail seachtrach a phróiseáil. Ós rud é an M6scriú moluibdínagus ní cheadaítear poll lárnach a bheith ag bolt M12 sa doiciméad próiseas, a chaithfear a chothromú ar deireadh le linn meaisínithe deil cothrománach.
The method of subsection processing is adopted in several vehicles, and a central hole is not drilled. Segmented processing Ф 12mm outer circle (M12 large end diameter) cut off; Segmented processing Ф 6mm outer circle (M6 large end diameter) is cut by turning cone. The procedure is relatively simple and is omitted here. It should be noted that Ф 6mm outer circle size machined to Ф 5.85- Ф 5.93mm is obviously conducive to threading. Outer circle greater than Ф 5.93mm has a large nesting allowance, which is prone to incomplete tooth profile such as thread slag dropping and lack of thread. Outer circle less than Ф 5.85mm, the extrusion deformation during threading is limited. If the size of the machine tool fluctuates, it is easy to make the large end size of the M6 thread close to the limit or out of tolerance. In addition, when cutting, the total length allowance shall be more than 1.5mm. To prevent the cutting knife from becoming blunt or the chip removal is not smooth, the slag on the conical surface (screw) at the root of the part can not be repaired after the end face is flattened. That is after the end face is flattened, the parts still have slag-dropping defects.
