Huizhou Pengchengrui Technology Co., Ltd.

The core manufacturing process of seamless nickel titanium alloy pipes is "melting and billet making → hot processing forming → cold processing finishing → heat treatment shaping → inspection and factory delivery". The key is to control the temperature and deformation to ensure the superelasticity and shape memory performance of nickel titanium alloy.

1. Raw material preparation and smelting for billet production

• Select high-purity nickel ingots and titanium ingots, and accurately mix them according to the nickel titanium atomic ratio (usually 50.5%~51% nickel).

• Using vacuum induction melting or vacuum arc melting to avoid oxidation, cast into nickel titanium alloy ingots.

• The ingot undergoes homogenization heat treatment (800~1000 ℃) to eliminate component segregation and prepare for subsequent processing.

2. Hot processing forming (core step, forming pipe blank)

• The ingot is heated to 850-1000 ℃ and extruded into a hollow tube blank to ensure no internal defects.

• Hot perforation or hot rolling of the pipe blank is carried out to further adjust the pipe diameter and wall thickness, forming the initial outline of the pipe material.

• The entire process is carried out under vacuum or inert gas protection to prevent high-temperature oxidation of the alloy.

3. Cold processing finishing (improving dimensional accuracy)

• Adopting cold rolling and cold drawing processes to gradually reduce diameter and wall thickness, with each deformation controlled at 10%~20%, to avoid excessive deformation leading to performance degradation.

• During the cold working process, intermediate annealing (400~600 ℃) is inserted to eliminate work hardening, restore material plasticity, and ensure the continuity of subsequent processing.

• Finally, the pipe is precision cold-rolled or polished to achieve the target outer diameter, wall thickness, and surface roughness (usually Ra ≤ 0.8 μ m).

4. Heat treatment shaping (ensuring core performance)

• Perform solution treatment (800~950 ℃, insulation for 10~30 minutes) on the finished pipes, rapidly cool them with water, and obtain a uniform martensitic structure.

• According to the requirements, perform aging treatment (300-500 ℃, insulation for 1-4 hours), adjust the phase transition temperature of the alloy (Af, As points), and ensure superelasticity or shape memory effect.

• Straighten the pipe after heat treatment to ensure its straightness.

5. Inspection and factory delivery

• Dimensional inspection: Check the outer diameter, wall thickness, ellipticity, etc. to ensure compliance with design tolerances.

• Performance testing: testing tensile strength, yield strength, hyperelastic recovery rate, phase transition temperature, etc.

• Defect detection: Internal cracks, inclusions, and other defects are inspected through ultrasonic and eddy current testing, and scratches and oxidation spots are checked through surface visual or fluorescent testing.

• Qualified products are cleaned, packaged, and completed before leaving the factory.

If you want to learn about the production process and market application of seamless nickel titanium alloy pipes, you can contact us at Wuge Nickel Titanium Alloy Materials.