Titanium balls (mostly made of TA1, TA2 pure titanium, and TC4 titanium alloy) are widely used in chemical, aerospace, and other fields due to their lightweight, high strength, and corrosion resistance characteristics. Its processing technology needs to adapt to the characteristics of titanium material such as poor thermal conductivity, easy tool sticking, and obvious work hardening. It is divided into three categories according to size: small (φ 3-10mm), medium small (φ 10-16mm), and medium large (φ 16-28mm). The core process is as follows:

1、 Raw material pretreatment

Select titanium ingots/rods that comply with the GB/T3620-2007 standard, purify them through vacuum melting (vacuum consumable arc melting VAR), reduce impurities such as oxygen and nitrogen, and avoid processing cracks. The surface of the rod is first machined and peeled to remove oxide scale and defects, ensuring the purity of the substrate.

2、 Ball forming (size based process)

Small/medium sized titanium balls (diameter 3~16mm): cold heading forming

At room temperature, the titanium rod is fed into a cold heading machine and high-pressure forged into a spherical blank through a mold, which has high efficiency and material utilization. After cold heading, the ball is treated with a light bulb to preliminarily correct the roundness, remove burrs and burrs, and obtain a regular ball blank.

Medium and large titanium balls (diameter 16-28mm): hot rolling+annealing

After heating the titanium rod to 800-900 ℃, it is hot-rolled to improve plasticity and avoid cracking; Subsequently, vacuum annealing (temperature 500-600 ℃) is carried out to eliminate hot rolling stress, refine grain size, and prevent deformation during subsequent processing.

3、 Heat treatment strengthening

After forming the ball blank, vacuum heat treatment is carried out: pure titanium balls are subjected to stress relief annealing, while titanium alloy balls (such as TC4) are quenched and tempered to improve hardness and strength while maintaining toughness and avoiding cracks during processing.

4、 Precision grinding and grinding (core precision link)

The accuracy (tolerance ± 0.005mm) and smoothness of titanium balls depend on multi pass grinding:

Hard grinding: rough grinding with a hard alloy grinding wheel to quickly correct dimensions and improve roundness;

Initial research: Grinding with coarse-grained abrasive (diamond/alumina) to reduce surface roughness;

Precision grinding (2 times): Fine grained abrasive is used for precise processing, ultimately achieving a mirror effect (Ra ≤ 0.02 μ m) without sand holes or cracks.

5、 Surface strengthening and flaw detection

Surface strengthening: It can be treated with nitriding/passivation to improve surface hardness and corrosion resistance. The passivation film can self heal after damage;

Non destructive testing: Ultrasonic/magnetic particle testing is used to detect internal cracks, inclusions, and other defects to ensure internal quality.

6、 Finished product testing and packaging

Detect dimensional accuracy, roundness, and surface roughness, clean and dry after passing the inspection, and vacuum package to prevent oxidation.