What is thread rolling and why is it mandatory for titanium fasteners?

Thread rolling is a cold extrusion process—not cutting—where hardened wheels compress a smooth rod so metal fibers flow and form raised threads in one pass. Titanium alloys and high-strength screws must be rolled never turned because cutting severs fibers and creates micro-cracks. BJCJTi operates an in-house thread-rolling line making it the only qualified threading method for its high-end titanium fasteners.

What is the full thread-rolling process for TC4 titanium screws?

BJCJTi's process runs: cuttingchamfering the rod stress-relief heat treatment surface cleaning then roll forming on a two- or three-axis machine with titanium-specific wheels and extreme-pressure lubricant. After forming parts get 100% inspection degreasing passivationsandblastinganti-seizing coating and gono-go gauging—ensuring stable 6g tolerance on every TC4 titanium screw.

How do rolled threads improve titanium fastener fatigue life?

Rolling keeps metal fibers continuous and creates a compressive stress layer at the thread root roughly doubling fatigue life versus machined threads it also yields a dense mark-free surface that resists seizing. BJCJTi's rolled TC4 threads thus survive vibrating shock-loaded joints where cut threads would crack and fail.

What challenges arise in titanium thread rolling and how are they solved?

TC4 is hard sticky and galling-prone challenges are tool adhesionburrs high extrusion resistance and surface folding. BJCJTi solves them with titanium-specific anti-adhesion rolling wheels high-pressure lubricant low-speed incremental feeding precise blank outer-diameter control proper chamfering and regular tool regrinding—preventing tears folds and micro-cracks.

Does BJCJTi perform in-house thread rolling with 100% inspection?

Yes. BJCJTi runs its own thread-rolling line and performs 100% inspection of tooth profile burrs surface folds and micro-cracks on every titanium fastener plus gono-go gauging. Combined with ISO9001:2000 and SGSTÜV validation this guarantees defect-free fatigue-resistant rolled threads for aerospace medical and automotive buyers.

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How is thread rolling performed during the production of titanium fasteners?

2026-04-28

The complete "rolling thread" process of titanium alloy fasteners

What is the best way to make small threads on titanium alloys (1)

What is the best way to make small threads on titanium alloys (2)

I. First, let’s clarify: What is thread rolling?

Thread rolling is not turning, nor is it cutting threads; it is a cold extrusion process. Using a pair or three sets of high-strength thread rolling wheels, the smooth rod is extruded and rolled, causing the metal fibers to flow along the thread profile and form raised threads through extrusion.

✅ Titanium alloys and high-strength screws must be thread rolled; they cannot be turned.

Translated with DeepL.com (free version)

II. Complete Thread Rolling Production Process for TC4 Titanium Screws

1. Pre-processing (Preparation Before Thread Rolling)

Cutting: Cutting titanium rods and machining blank bars on a lathe

Chamfering: Chamfering the end face of the screw head and the thread ends (to prevent tool breakage and thread damage during thread rolling)

Heat Treatment / Stress Relief: TC4 material is hard; machining stresses must be eliminated in advance

Surface Cleaning: Degreasing and deburring to ensure smooth thread forming

Critical: The screw’s outer diameter must be precise prior to thread rolling, slightly smaller than the thread mean diameter to allow for forming allowance

2. Complete Roll Forming Production Process for TC4 Titanium Screws

Pre-processing (Preparation before roll forming)
Machine Setup and Clamping

Equipment: Two-axis roll forming machine / Three-axis thread rolling machine

Tooling: Custom roll forming wheels specifically designed for titanium alloy (high hardness, wear-resistant, anti-adhesion to titanium)

Setup:

Adjust the center distance between the two wheels to control thread pitch and profile

Adjust feed rate and rolling time

Apply extreme-pressure thread rolling oil / specialized titanium alloy lubricant

3. Core: Principles of Thread Rolling for Titanium Parts

Two thread-forming rollers rotate in the same direction.

A bare titanium rod is placed between the two rollers.

The rollers slowly compress the workpiece, and the friction causes the rod to rotate on its own axis.

Through continuous radial compression, the metal flows outward and accumulates.

The thread root is compressed, and the thread crest is raised, forming a complete thread in a single pass.

Key Points (Exclusive to Titanium Alloys)

TC4 material is hard, sticky, prone to scoring, and prone to galling:

Feed rate must not be too fast

Pressure must not be applied too abruptly

High-quality lubricant must be used to prevent thread surface tearing, folding, tool marks, and microcracks

4. Immediate Results After Roll Forming

The metal fibers in the thread remain continuous (unlike conventional thread cutting, which severs the fibers)

A compressive stress layer forms at the thread root → Doubling fatigue life

The thread surface is dense, smooth, and free of cutting marks

The thread profile is full and precise, with a stable 6g tolerance

5. Post-processing

Blank removal and automatic unloading

100% inspection: tooth profile, damaged teeth, burrs, surface folds, microcracks

Degreasing and cleaning → Passivation / Sandblasting / Anti-seizing coating

Dimension inspection using go/no-go gauges (go gauge passes, no-go gauge fails)

III. Titanium Rolled Threads vs. Conventional Machined Threads (Why Titanium Must Be Rolled)

Fiber Structure

Rolled Threads: Fibers completely wrap around the thread, providing high toughness

Machined Threads: Fibers are severed, with tool marks and micro-cracks at the thread root

Fatigue Resistance

Rolled Threads: Compressive stress, shock-resistant and fracture-resistant, suitable for vibrating environments

Machined Threads: Prone to fracture from cracks at the thread root, rendering the titanium part immediately unusable

Surface Quality

Rolled Threads: Smooth with no tool marks, no folds, and no micro-cracks

Machined Threads: Numerous deep and shallow tool marks, posing significant risks of corrosion and fatigue

Anti-Seizing

Rolled threads have a dense surface layer, ensuring smoother engagement and reducing the likelihood of seizing

IV. Three Key Challenges in Titanium Alloy Thread Rolling & Their Solutions

Titanium material sticks to the tool and is prone to burrs → Specialized titanium alloy thread rolling wheels + high-pressure lubricating oil

High hardness and significant extrusion resistance → Low-speed rolling, incremental feeding, and avoiding full penetration in a single pass

Prone to surface folding and peeling → Precise control of the blank’s outer diameter + proper chamfering + regular regrinding of tooling

V. Summary in a Nutshell

Thread rolling for titanium alloy fasteners is a cold extrusion plastic forming process in which a thread rolling die compresses a smooth bar blank, causing the metal to flow naturally and form threads. This process does not sever the metal fibers, and compressive stress is created at the thread root, resulting in TC4 titanium screws with high thread strength, defect-free surfaces, fatigue resistance, and fracture resistance. It is the only qualified threading method for high-end titanium fasteners.