What is Cryogenic Treatment?
Cryogenic treatment describes a very low-temperature processing step used within some steel heat-treatment schedules. In blade manufacture, related sub-zero treatments can help transform retained austenite after hardening. Their effect depends on the grade and complete processing sequence; a treatment name or minimum temperature alone does not establish finished-scissor performance.
Keep a translated term attached to language and scope
Technical vocabulary can shift by maker, market, era, and component; preserve the original term before mapping it. Apply to What is Cryogenic Treatment?
- 01 Original Retain script, romanization where useful, and literal wording.
- 02 Source Record maker, catalog, curriculum, standard, market, and date.
- 03 Scope Name the part, geometry axis, process, technique, or trade context.
- 04 Map carefully Show overlap and disagreement instead of forcing one English synonym.
Do not inferA dictionary translation or shared characters cannot prove that two makers, countries, components, or techniques mean the same thing.
What is Cryogenic Treatment?
Why It Matters for Scissors
Some austenite can remain after steel is quenched. Its amount and response to further cooling depend on the alloy and preceding treatment. Alleima’s 14C28N datasheet explains how unsuitable hardening conditions can produce excessive retained austenite and lower hardness. This is evidence about a specified steel, rather than a finding that all scissor blades have a damaging amount.
For a buyer, the useful connection is between the treatment claim and the exact model. Ask whether a quoted number describes the cooling stage, final hardness or a comparative cutting test. These answer different questions. A temperature cannot substitute for a finished-blade measurement, and a hardness result cannot by itself establish how long that scissor will cut satisfactorily.
Published examples with their original scope
| Source | Published treatment detail | Where it applies |
|---|---|---|
| Alleima knife-steel guide | Hardening programs include −20 °C or −70 °C cooling | The named steel and program; not a scissor-wide schedule |
| ZWILLING Japanese knife guide | FRIODUR at −70 °C or below; CRYODUR at −196 °C | Its knife-manufacturing explanation |
| Jaguar 2025 catalog | FRIODUR blade treatment at −180 °C | The catalog’s scissor account |
| Proterial ZDP-189 page | Sub-zero treatment listed in the grade schedule | Producer material processing; no sub-zero temperature or duration supplied there |
| Mizutani US material account | Extramarise I and II involve sub-zero processing | Named maker materials; a full schedule is not supplied there |
Sources: Alleima deep-freezing guide, ZWILLING knife production, Jaguar 2025 catalog, Proterial ZDP-189 and Mizutani US.
The same treatment word can appear in different product contexts. Keep the company, product and document together when comparing these figures. “Ice-hardened,” “sub-zero” and “cryogenic” are not interchangeable alloy designations, and the table does not rank the implementations.
Technical Detail
Transformation and the rest of the cycle
The martensite transformation can continue as temperature falls after quenching. Whether further cooling is useful depends on the steel’s starting condition and the amount of austenite remaining. A published schedule therefore needs to be read as a sequence: hardening conditions, quench, any sub-zero step and subsequent tempering. Changing one part can change the result.
Alleima’s knife-steel guide describes deep-freezing before tempering and reports a hardness increase alongside a slight toughness reduction in its stated context. It also shows a 12C27 example. Those observations should retain the alloy and treatment context; they do not give an HRC increase for every scissor described as cryogenic.
Why a universal recipe is misleading
A general glossary cannot specify one cooling rate, holding period or warming rate for every blade. The public maker examples above do not collectively form a validated processing schedule. A published endpoint temperature leaves the time, atmosphere, section thickness and relationship to tempering unresolved unless the source supplies them.
For ZDP-189, Proterial lists annealing, quenching, sub-zero treatment and tempering in its material schedule. The ZDP-189 reference keeps the published conditions and their limits together. It is an example of a grade-specific record, not evidence that ZDP-189 is the only blade steel with such documentation.
Reading performance and stability claims
To assess a claim about dimensional stability, carbide changes or edge life, look for the material identity, treatment sequence, test method and untreated comparator. A mechanism proposed for a laboratory tool-steel sample is not automatically a measured result for a salon scissor. A statement about reduced retained austenite needs its own measurement if a particular percentage is claimed.
Practical comparison
Use treatment information alongside the exact scissor’s construction, edge and intended technique. Keep the maker’s care and service instructions with the listing. Sub-zero treatment during manufacture is not a maintenance step for an assembled tool, and neither its name nor its temperature supplies a sharpening interval.
Related Terms
Sources
The producer and maker sources linked beside the table distinguish knife guidance, scissor documentation and material processing. Reviewed 30 September 2026. Jaguar’s catalog was verified through indexed text; the full PDF could not be fetched during this review. Its temperature is retained as an attributed catalog statement, without adopting the catalog’s proposed mechanism or durability claims.
See Also
Sources
6 sources- Alleima 14C28N Material Datasheet (manufacturer official)
- Alleima: Deep-freezing of knife steel (manufacturer official)
- 🇯🇵 ZWILLING: Knife production and hardening (manufacturer official)
- Jaguar Collection 2025 (manufacturer official)
- Proterial / Yasugi Specialty Steel (旧日立金属・安来鋼) (manufacturer official)
- Mizutani Scissors — North America (manufacturer official)
Frequently Asked Questions
3 answers you can open one at a timeDo all scissor steels need cryogenic treatment?
No universal requirement follows from the word scissors. Use the exact grade’s processing specification and the maker’s product documentation. Proterial (formerly Hitachi Metals) includes a sub-zero step in its ZDP-189 schedule; that does not establish the schedule for another alloy or finished model.
Is a colder cryogenic treatment always better?
Temperature alone cannot rank treatments. ZWILLING publishes different temperatures for FRIODUR and CRYODUR in its knife documentation, while Jaguar describes a separate FRIODUR implementation for scissors. Steel, preceding heat treatment and subsequent tempering all affect the result.
Does ice-tempered mean that tempering happens below zero?
The marketing label does not identify a complete metallurgical schedule. Distinguish the cooling step from subsequent tempering, and retain the manufacturer’s terminology with the actual product and source. Do not infer a shared alloy or temperature from a treatment name.
Comments & questions
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