Application And Characteristics Of Tantalum Tube

Sep 19, 2019

Tantalum tube cannot be processed in the same way as ordinary metals. The general process is forging processing heat treatment, with hammer and stamping two ways to make flat slab or round medium and small blank.

Tantalum tube manufacturing process editing

Breakdown

Tantalum cannot be processed in the same way as ordinary metals. The general procedure is forging, processing and heat treatment.

The flat slab or round medium and small blank can be made by hammering and punching. Unlike ordinary metals, tantalum cannot be processed hot. The recrystallization temperature of tantalum exceeds 1000~C. If heated, excessive oxidation will occur even if the general protective coating is made. What is more serious is that if tantalum is exposed to such a high temperature, not only will the surface of tantalum undergo excessive oxidation, but also oxygen can invade the atoms inside the matrix and make tantalum brittle. Not only oxygen, but even nitrogen, carbon and hydrogen can make tantalum brittle. Due to the above reasons, tantalum is generally not hot processed. When necessary, a protective coating or an inert gas atmosphere shall be applied.

Heat treatment

Since tantalum reacts actively with oxygen, it must be avoided in an atmosphere where even a little air is present

Heat treatment. Therefore, almost all annealing is done in a high vacuum and the furnace must be highly airtight. Generally, the heat treatment temperature of tantalum is generally 950~1300℃, and tantalum and commonly used tantalum alloy do not undergo phase transformation within this temperature range. Heat treatment is only used for annealing, so neither heating temperature nor cooling speed is important. In order to produce complete recrystallization, the heat treatment time is slightly longer.

Commercially produced tantalum has a high purity. The grains become very large by annealing. The size of crystal particles is determined by cold working, purity, temperature and process steps. Therefore, temperature control and process control are important means to determine the size of crystallization.

Unlike many other metals, tantalum must be very clean before heat treatment. If not cleaned very clean, will occur by hydrogen, oxygen, nitrogen and carbon surface pollution, become embrittlement (hardening) tissue. Since hydrogen, oxygen, nitrogen and carbon are very active infiltrating elements within the annealed temperature range of tantalum, once contaminated by these elements, no other way can be removed except re-smelting.

Tantalum plate manufacturers manufacturing characteristics

Tantalum plate manufacturers almost all adopt cold processing. Generally, tantalum ingots of 15 ~ 30cm are cold-forged into slabs of about 8~10m thickness, which are then cold-rolled with a compression ratio of over 95%. In commercial production, the slab is usually rolled to 0 on two or four rollers. 63-1. 2cm thick plate, width is generally 51 ~ 102cm. Typical rolling is performed at room temperature or near room temperature to prevent oxide formation on the surface. When hot rolling is required, the temperature rises to 1000℃ due to recrystallization, and intense oxidation reaction occurs.

Almost all plates are annealed in vacuum. Since there is no phase metamorphosis, the rate of heating and cooling is not important. Further rolling is carried out with an ordinary mill, in which case a 4-roll multi-roll mill is generally used. Since tantalum is very soft, care should be taken to prevent scratches during processing and transportation.

Tantalum rod manufacturing features

To make a rod, the material is first forged or extruded to a moderate size in the middle, with a representative cross sectional yield of 70-90%, and then annealed. When reprocessed, a forging, rolling, extrusion, or drawing process is usually used. Wire using the ordinary shape of the wire drawing machine for processing. Because tantalum material is very soft, it is easy to scratch, and the surface problem in drawing is very big, the manufacturer should pay special attention to the surface condition and lubrication. ,

Tantalum tube manufacturing characteristics

Tantalum can be made into welded and seamless tubes and has a wide range of USES. Seamless tubes are made by extrusion, tube reduction, or deep drawing with sheet metal. The welding is made by forming a strip, then forming a tube, and welding the joint with a gas tungsten arc (GTAW).

Advantages and disadvantages of tantalum seamless tube and welded tube

Welded pipe

advantages

1: Uniform wall thickness, good quality of inner surface

2: High production efficiency. The cost is low

3: Easy to produce large diameter pipe

4: Short production cycle

Product quality is easy to control

Disadvantages

1: Poor flexibility, not suitable for production specifications and small batch of products

2: Weld is often the weak link

3: Weld cleaning is difficult

4: The ovality is not easy to control

5: High requirements for dimensional accuracy of the used strip

Generally suitable for the production of large quantities of products

Seamless tube

advantages

1: Can produce small specifications of tube and capillary material

2: Good flexibility, suitable for the production of small batch, specifications of the product.

3: The performance of each part of the pipe is even

disadvantages

1: Uniformity of wall thickness is difficult to control

2. Long production cycle and low yield

3. Complex equipment and large investment

4: Difficult to produce large diameter pipe

Generally suitable for the production of small batch specifications of more products