金屬成形 (Metal forming)

Metal forming: (mechanical deformation)

金屬成型：（基於機械變形）

The forming process involves large (typically compressive) stresses (exceeding yields strength, deforming strength of the metal) to change the shape of the workpiece through plastic (non-recoverable) deformation. Large forces are exerted on the workpiece by a press or hammer through tools called "dies". The desired final part shape may be achieved by using a sequence of progressively shaped dies and loading cycles

成形過程涉及大的(通常為壓縮的)應力(超過金屬的屈服強度①，變形強度)，以通過塑性(不可恢復)變形改變工件的形狀。通過稱為「模具」的工具，壓力機或鎚子在工件上施加很大的力。可以通過使用一系列漸進成形的模具及載入循環，來實現最終期望的零件形狀。

Metals used in forming processes should have low yield strength (high malleability and high declivity) to accommodate large plastic deformation without breaking) these properties may be temperature dependent. Lubricants (oil or soap) may be used on dies to minimize friction and wear.

成形工藝中使用的金屬應具有低屈服強度（高延展性和高傾斜度）以適應大的塑性變形而不斷裂)，這些性能可能取決於溫度。可將潤滑劑（油或肥皂）用於模具上，以減少成形過程中的摩擦和磨損。

Heating metal workpiece allows accomplishment of metal forming processes with lower forces and power consumption, but the final part is generally of poorer quality.

加熱金屬工件可以以較低的力與功耗完成成形過程，但最終零件通常質量較差。

Cold working (Room temperature)

Good accuracy, surface finish, repeatability
Strain hardening increase part strength
Controllable directional strength properties of part
Requires high deformation forces, only limited changes in part geometry achievable for each die set.

冷加工 (室溫下)

精度好，表面光潔度好，可重複性好
應變硬化②提高零件強度
零件的可控方向強度特性
需要高變形力，每個模組只能實現零件幾何形狀的有限變化。

Hot working (50%-75% of Tm, Kelvin scale melting temperature) Above "recrystallization" temperature internal structure of metal can reorganize

Requires lower forces than cold working & substantial deformations are possible
May be feasible for metals that are brittle at room temperature
Isotropic strength properties
No strain hardening improvement of length
Poor accuracy, surface finish and repeatability

熱加工（50%-75%的Tm，開爾文標度熔化溫度）高於「再結晶」溫度的金屬內部結構可以重新組織。

需要比冷加工更低的力，並且可能會產生較大的變形。
對於在室溫下易碎的金屬，是可行的。
各向同性強度特性
長度無應變硬化改善
精度差、表面光潔度和重複性差

Warm working: intermediate process; heat part to ~30% of Tm

Force application (forging press or hammer) determines strain rate of forging process ε = v/h

ε can reach values up tp 1000/sec

熱加工（中間工序）：將零件加熱至~30% Tm

施加力(鍛壓機或鎚子)決定鍛造過程的應變速率ε=v/h。

ε可以達到tp 1000/sec以上。

Typical forming methods:

Bulk deformation processes for parts with low surface area/volume (A/V) ratios - forging, rolling, extrusion, drawing.
Sheet metal forming (presswork or stamping) - for parts with high A/V ratio.

典型的成形方法：

低表面積/體積比(A/V)零件的體積變形工藝-鍛造、軋制、擠壓、拉伸。
金屬板成形（印刷或衝壓）-用於具有高A/V比的零件。

Forging: Compression of a workpiece between two halves of a die defining desired part shape.

Usually a hot-working process, but some parts can be cold-forged. Dated to ~5000 BC (used to make coins, weapons, jewelry, etc.). Forging parts often require finishing processes (e.g. machining or heat treatment)

鍛造：在模具兩半之間對工件的壓縮，以決定所需零件的形狀。

通常採用熱加工工藝，但有些零件可以冷鍛。公元前5000年（用於製造硬幣、武器、珠寶等）鍛造零件通常需要精加工工藝（如機械加工或熱處理）

Deformation force: force may be applied gradually (forging process) or as an impact load (forging hammer) using open dies, impression dies, or flashless dies.

變形力：可以使用開口模具，壓印模具或無閃光模具逐漸施加力（鍛造過程）或作為衝擊載荷（鍛造錘）。

Open dies allow lateral flow of workpiece, while impression dies significantly constrain workpiece shape. Flashless dies prevent flow of excess metal along "parting line" between two die halves - this is called "flash", which must be machined off in flashless forging, workpiece volume must be precisely matched to die cavity volume to prevent underfill or overfill.