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英语翻译
Cubic boron nitride（CBN）and polycrystalline cubic boron nitride（PCBN）inserts have traditionally been the tools of choice for hard-turning applications.But,they are considered too costly for many operations.The cryogenic machining technique also allows greater use of low-cost ceramic inserts for hard-turning operations.
CBN and PCBN ceramic inserts tend to wear unevenly and prone to fracturing when hard turning dry or with water or oil-based coolants.Incresed fracture toughness resulting from low-temperature liquid nitrogen cooling provide more predictable ,gradual flank wear also allows alumina ceramics inserts to be used in the critical finishing operations.
The liquid nitrogen may be stored in a small ,dedicated cylinder near a machine,or in a supply tank that would serve multiple machines.Programming is similar to a traditional coolant delivery system.A flexible liquid nitrogen line attaches to a lathe’s turret via a rotational coupling.This line feeds a delivery nozzle clamped to the tool,which directs the liquid nitrogen to the insert tip.
Cubic boron nitride（CBN）and polycrystalline cubic boron nitride（PCBN）inserts have traditionally been the tools of choice for hard-turning applications.But,they are considered too costly for many operations.The cryogenic machining technique also allows greater use of low-cost ceramic inserts for hard-turning operations.
CBN and PCBN ceramic inserts tend to wear unevenly and prone to fracturing when hard turning dry or with water or oil-based coolants.Incresed fracture toughness resulting from low-temperature liquid nitrogen cooling provide more predictable ,gradual flank wear also allows alumina ceramics inserts to be used in the critical finishing operations.
The liquid nitrogen may be stored in a small ,dedicated cylinder near a machine,or in a supply tank that would serve multiple machines.Programming is similar to a traditional coolant delivery system.A flexible liquid nitrogen line attaches to a lathe’s turret via a rotational coupling.This line feeds a delivery nozzle clamped to the tool,which directs the liquid nitrogen to the insert tip.
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