The processing technology and precautions of titanium and titanium alloy titanium rod and titanium p

Cutting processing of titanium:

The cutting performance of titanium is moderately difficult, similar to stainless steel. The cutting performance of titanium is related to the basic physical and chemical properties of titanium. Based on many years of practical experience combined with various reference documents, Shenzhen Sanliu Titanium Industry Co., Ltd. summarizes the following difficulties in the processing of titanium alloy titanium rods and titanium alloy mold titanium plates:

① Due to the low thermal conductivity of titanium, the frictional heat generated at the tool tip is almost concentrated on the blade and the forward inclined surface of the tool. The tool tip has high temperature and is easy to wear.

② Due to the small modulus of elasticity, the workpiece is easy to bend during deep cutting, so an anti-vibration frame must be installed during machining.

③ Due to the large springback and obvious material anisotropy, the machining accuracy will be affected.

④ Due to the strong chemical activity at high temperature, surface pollution is prone to occur during processing.

⑤ Due to the high hardness of the titanium surface oxide layer and getter layer, the tool wear is serious.

According to the above situation, titanium cutting should follow the following basic principles:

① Use low-speed processing. Generally, the cutting speed of titanium should be 25%-50% or lower than that of steel of the same hardness.

② Use large feed rate. The main purpose is to avoid friction between the tool and the hard surface. The amount of feed has little effect on the temperature rise.

③ Use sharp knives. Once the tool becomes blunt, it must be replaced immediately.

④ Adopt sufficient cutting fluid (lubricating coolant). Commonly used cutting fluids include 5% sodium chloride solution, 5%-10% water-soluble oil aqueous solution, emulsified oil, vulcanized oil, and engine oil.

1) Turning Titanium turning should use high-speed steel or cemented carbide tools, and good rigid machine tools and fixtures should be used. The cemented carbide should not contain titanium. When using cemented carbide tools, the cutting speed is generally 30~55m/min. When turning dry, use a lower speed, and when turning wet, use a higher speed. Standard emulsion can be used as cutting fluid. In addition, live centers must be used when turning titanium, not dead centers. This is because when the titanium rubs against the dead center, it heats up and sticks, causing the thimble hole to expand and deviate, which affects the machining accuracy.

2) Planing Titanium planing is more difficult than turning. The impact and vibration when dragging the knife and eating the knife are prone to chipping. K30 (YG8) cemented carbide is the best choice for planer material. The cutting speed for industrial pure titanium is about 12m/min. If high-speed steel tools are used to cut soft and hard titanium alloys, the planing speed should be reduced to less than 5m/min. When rough planing, the cutting depth should be less than 6mm, and the horizontal cutting speed should be 2mm/pass. During fine planing, the cutting depth should be reduced to 0.5~0.05mm/min, and the horizontal cutting speed can be increased to 12~25mm/pass.

3) Milling Milling of titanium and titanium alloys is more difficult than turning. High-speed steel or cemented carbide tools should also be used for milling, and milling cutters with a small diameter and a large number of teeth should be used for down milling to reduce deflection and vibration. The milling fluid should generally be lubricating and cooling fluid that dissolves water, and the addition method is spray Shape spray is better. When using cemented carbide tools for milling, the milling speed can reach 50m/min; when using high-speed steel tools, the milling speed is reduced by about 40%.

4) Drilling Drills for titanium and titanium alloy drilling can be made of high-speed steel or hard alloy, and it is better to use a double apex angle of 118° or 90°, because it can cut off the chips to make it easier to remove chips. If the chips are not removed in time, the bit will be stuck, broken, stuck, etc. The drilling speed of pure titanium can reach 20-30m/min, while the drilling speed of titanium alloy should be less than 10m/min.