高壓冷卻對切削中碳鋼之影響研究

工具機在電腦補助設計與控制的出現後呈現大幅度的進步，依靠電腦的運算能夠排除許多人為失誤所造成的影響。然而部件切削精確率與良率深受物理現象特性的牽制，影響的範圍包含工件的材質、刀具的種類與切削過程所伴隨的高溫。其中切削時刀具與工件所產生的高溫是困擾業界許久的問題。高溫除了會壞刀具與部件外，其次因部件材質特性而導致段屑過長、沾黏等現象，嚴重時可能會產生纏屑以及刀具壽命縮短等問題。為此在切削的過程中噴濺切削液是一個廣為業界使用的解決方案，藉由切削液潤滑刀具與工件的接觸點，進而降低熱點溫度，減少高溫帶來的種種問題。然而使用切削液仍有其瓶頸，依照工件的材質而定，當切削速率到達一定程度時，切削液所能產生的效果有限。再者熱點的溫度過高時會與切削液產生萊頓弗羅斯特現象，產生的蒸氣膜會阻礙切削液附著於熱點上，在無法降溫且維持高速率切削的情況下，纏屑、沾黏與刀具壽命縮短等問題再次浮現，不得已得降低切削速率或者給料的頻率，因而降低整體產能。本篇論文藉由在不同材質的加工材料，如鍛鋁、鎳基合金、鈦合金與S48C中碳鋼進行有高壓噴流與無高壓噴流的加工下，所產生的不同切屑情況進行探討分析，最後選用S48C中碳鋼在連續加工下，紀錄加工尺寸的變化與刀具壽命的情況，對於高壓噴流的加工運用，為印證使用高壓噴流後，切削液對刀具與加工部件能進行降溫的解決方案，透過高壓手段使切削液能突破萊頓弗羅斯特現象的蒸氣膜，使其能夠直接對熱點產生作用，進而達到降低溫度的效果，佐證使用高壓噴流可以為改善加工品質與刀具壽命的驗證。

關鍵字

高壓噴流；高溫；難切削材；萊頓弗羅斯特現象

並列摘要

Machine tools in the computer subsidies design and control after the emergence of significant progress, relying on computer computing can exclude many people caused by the impact of errors. However, the precision and yield of parts are well constrained by the physical phenomena. The scope of the influence includes the material of the workpiece, the type of the tool and the high temperature accompanying the cutting process. Which cutting the tool and the workpiece produced by the high temperature is troubled by the industry for a long time. In addition to the high temperature will be bad tools and parts, and secondly because of the material characteristics of the parts lead to too long segment, sticky and other phenomena, serious may produce cuttings and tool life shortages and other issues. To this end in the process of cutting spilled cutting fluid is a widely used in the industry solution, by cutting fluid lubrication tool and workpiece contact points, thereby reducing the hot spot temperature and reduce the heat caused by various problems. However, the use of cutting fluid is still its bottleneck, according to the material of the workpiece may be, when the cutting rate reaches a certain level, the cutting fluid can produce the effect is limited. In addition, when the temperature of the hot spot is too high, it will produce the Leiden Frost phenomenon with the cutting fluid, and the resulting vapor film will prevent the cutting fluid from adhering to the hot spot. When the temperature is not cool and the high speed cutting is maintained, And tool life shortages and other problems emerge again, forced to reduce the cutting rate or feed the frequency, thus reducing the overall capacity. In this paper, the paper analyzes the different chips produced by high pressure jet and high pressure jet in different materials, such as forging aluminum, nickel-based alloy, titanium alloy and S48C medium carbon steel. Finally, The use of S48C in the continuous processing of carbon steel, record the size of the changes in processing and tool life, the use of high-pressure jet processing, to confirm the use of high-pressure jet, the cutting fluid on the tool and processing components can be cooling solution, through High pressure means to make cutting fluid break through the Leiden Frost phenomenon of the vapor film, so that it can directly affect the hot spots, and thus achieve the effect of reducing the temperature, supporting the use of high pressure jet can improve the processing quality and tool life verification.