Amorphous Metal Watch Components Through Hot Drawing and Machining

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing methods for manufacturing watch components are limited by the inability to effectively utilize non-magnetic, high-strength amorphous metals due to their poor machinability and fragility, which are critical for watch components like balance wheels and escape wheels that are sensitive to magnetic fields and require precise machining.

Innovation Solution

A method involving hot drawing and machining of bulk amorphous metallic glass alloys to produce watch components such as balance shafts, including steps like preform creation, hot drawing, machining, and tribofinishing, to achieve non-magnetic, high-strength components with precise dimensions.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Strength

If amorphous metallic glass alloys are used to manufacture watch components, then non-magnetic properties and high strength are improved, but machinability deteriorates due to fragility

Engineering Contradiction:

Improvehigh strengthVSAvoidmachinability

Core Design Contradiction:

StrengthVSEase of manufacture

Solution Approach 1:

The patent applies parameter changes by heating the amorphous metallic glass to its supercooled liquid state (between Tg and Tx temperatures) to temporarily alter its mechanical properties. This allows the material to transition from a brittle solid state that cannot be machined to a ductile supercooled liquid state that can be easily formed and machined, then cooled to regain its high strength and non-magnetic properties.

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The patent utilizes phase transitions of the amorphous metallic glass material. The material is heated through its glass transition temperature (Tg) and crystallization temperature (Tx) to enter the supercooled liquid state, where it exhibits different mechanical properties enabling machining. After forming, rapid cooling returns the material to its amorphous solid state with high strength and non-magnetic characteristics.

Inventive Principle:

Principle #36Phase transitions

2Ease of manufacture

If traditional hardenable free-cutting steel is used, then machinability is good, but magnetic sensitivity deteriorates

Engineering Contradiction:

ImprovemachinabilityVSAvoidmagnetic sensitivity

Core Design Contradiction:

Ease of manufactureVSObject-affected harmful factors

Solution Approach 1:

The patent changes the physical state parameter of the amorphous metallic glass by heating it to the supercooled liquid range, transforming it from a brittle material to one with ductile properties suitable for machining. This temporary parameter change enables traditional machining operations to be performed on normally un-machinable material.

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The patent employs amorphous metallic glass as a composite material system that combines multiple desirable properties: non-magnetic characteristics, high strength, and (when processed through supercooled liquid state) improved machinability. The material composition is specifically designed to exhibit these composite properties.

Inventive Principle:

Principle #40Composite materials

3Strength

If amorphous metallic glass is machined in solid state, then material strength is maintained, but manufacturing precision deteriorates due to brittleness

Engineering Contradiction:

Improvematerial strengthVSAvoidprecision

Core Design Contradiction:

StrengthVSManufacturing precision

Solution Approach 1:

The patent utilizes phase transitions by heating the amorphous metallic glass above its glass transition temperature (Tg) but below its crystallization temperature (Tx) to enter the supercooled liquid state. In this state, the material becomes ductile and can be precisely machined without brittleness-induced errors, then rapidly cooled to lock in the precise dimensions while maintaining high strength.

Inventive Principle:

Principle #36Phase transitions

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

Enables the production of non-magnetic, high-strength watch components with excellent mechanical properties, resistance to magnetism, and precise tolerances, overcoming the limitations of traditional materials like hardenable free-cutting steel.

Implementation Method 1

heating the amorphous alloy to a temperature between its glass transition temperature (Tg) and its crystallization temperature (Tx)

Methodology Applied

Scientific EffectGlass transition:

Implementation Method 2

the amorphous alloy is heated to a temperature between its glass transition temperature (Tg) and its crystallization temperature (Tx) so as to bring the amorphous alloy into a supercooled liquid state

Methodology Applied

Scientific EffectSupercooled liquid state: Supercooling

Implementation Method 3

the molten alloy is injected into a cooled mold to obtain an amorphous structure

Methodology Applied

Scientific EffectRapid cooling: Cooling

Implementation Method 4

fabrication of bulk amorphous zirconium and/or hafnium alloys

Methodology Applied

Scientific EffectAmorphous structure formation: Vitrification

Data Source

PatentEP4700497A1Method of manufacture of a watch_making component

Publication Date: 2026.02.25 ROLEX SA

Figure 1~3
Figure 4

AI summary

Method for making a watch component (100) in amorphous metal alloy, the manufacturing process comprising: - a step (E1) of making a first preform in amorphous metal alloy, then - a step (E2) of hot drawing of the first preform to obtain a second preform, then - a step (E3) of machining of the second preform.