What Is The Difference Between Hot-Rolled And Cold-Rolled Titanium Grade 5 Plates?

Ti Grade 5 is currently the most widely used and most versatile titanium alloy sheet. It is usually produced via two processes: hot rolling and cold rolling, which differ significantly in processing routes, microstructure & properties, and applicable working conditions.

1. Hot Rolling Process

Process flow: Ti Grade 5 ingot → surface cleaning → high-temperature holding → high-pressure water descaling → rough rolling for breakdown → multi-pass finish rolling → cooling and straightening → shearing and flaw detection → warehousing

Advantages: Dynamic recrystallization occurs during rolling, which refines as-cast coarse grains and repairs internal defects. It features large single-pass reduction and high production efficiency, and can produce medium and thick plates with a thickness ranging from 3mm to over 100mm.

Alloy-specific key points: Ti-6Al-4V is prone to forming a hard oxide layer at high temperatures, so dual descaling combining pickling and sand blasting is required. Thick plates need stress relief annealing after rolling to prevent cracking during bending and welding.

2. Cold Rolling Process

Process flow: Grade 5 hot-rolled billet → pickling for oxide scale removal → multi-pass cold rolling with small reduction → degreasing and cleaning → vacuum bright annealing → straightening, slitting and polishing to obtain finished products

Features: The plate surface is free from high-temperature oxidation, with high smoothness and excellent dimensional accuracy. The single-pass deformation is small, and continuous work hardening occurs during rolling, so multiple annealing treatments are required to restore plasticity.

Alloy-specific key points: Grade 5 exhibits more obvious work hardening than pure titanium Grade 2, requiring more rolling passes and annealing cycles. Ultra-thin plates are treated with vacuum annealing to avoid oxygen and hydrogen absorption, meeting the cleanliness requirements of the aviation and medical industries.

1. Specification and Dimensional Accuracy

Hot-rolled: Medium and thick large plates of 3–100mm, with a thickness tolerance of ±0.3~0.8mm, general plate flatness, and oxidized burrs on edges. It is suitable for low-precision structural parts.

Cold-rolled: Thin/ultra-thin plates of 0.1~4.76mm, with a thickness tolerance ≤±0.05mm, flat surface and stable dimensions. It is adaptable to precision machining in aviation and medical fields.

2. Metallographic Structure and Mechanical Properties

Hot-rolled products: High-temperature recrystallization forms equiaxed fine grains, with low residual stress and good elongation, as well as excellent bending, stamping and welding properties, but relatively low strength and hardness. They are mostly used for large welded plastic components.

Cold-rolled products: Grains are elongated by rolling, and the structure becomes dense after annealing. In the unannealed hardened state, strength, hardness and wear resistance are greatly improved, but plasticity is reduced, making them unsuitable for deep bending.

3. Surface Quality

Hot-rolled plates: An oxide layer forms at high temperature. After descaling, the surface is rough and matte, with pitting and color difference. Additional polishing is required for a bright appearance.

Cold-rolled plates: Free from high-temperature oxidation, the plate surface is fine and smooth, with a natural bright finish after vacuum annealing. It has high cleanliness, no hydrogen embrittlement or impurity contamination, and can be used directly.

• Aerospace: Landing gear bases, fuselage load-bearing frames, engine casings, thick-walled rocket components.
• Marine equipment: Deep-sea pressure-resistant cabins, seawater pipeline flanges, offshore wind power supports.
• Chemical anti-corrosion equipment: High-pressure reactors, heat exchanger tube sheets, acid-base tank linings.
• Military engineering machinery: Light armor, hydraulic pressure-bearing valve bodies, equipment load-bearing brackets.

• Aviation precision parts: Fighter skins, wing lining plates, instrument housings, flow guide thin plates.
• Medical implant consumables: Orthopedic steel plates, implant base materials, surgical instrument plates.
• New energy precision electronics: Solid-state battery packaging plates, sensor housings, vacuum chamber lining plates.
• Precision anti-corrosion accessories: Aviation sealing gaskets, instrument panels, high-end decorative plates.

Ti Grade5 is the mainstream titanium alloy. Hot rolling and cold rolling are not superior or inferior to each other; they are only adapted to different thicknesses and application scenarios.

Choose hot-rolled plates when: the thickness is above 3mm, the part is a large structural component, bending/rolling/welding processing is required, cost control is prioritized, and there is no high requirement for surface quality.

Choose cold-rolled plates when: thin/ultra-thin plates are needed, precision assembly is required, the scenario has high cleanliness requirements such as medical and aviation fields, and high precision and high surface smoothness are demanded.

Composite processing scheme: Use hot-rolled plates for rough forming of large parts, and match cold-rolled thin plates in precision assembly areas to balance cost, formability and precision.

Ruihang, as a direct manufacturer of titanium products, supply optimal quality raw materials for your precision components production. If you have any purchasing needs for Gr5 Titanium Plates, please feel free to contact us via email: Sam.Rui@bjrh-titanium.com