The material your hair cutting shears are made from determines how long they last without sharpening and how fine the edge of them can be. Of course, the way you are taking care of your shears has an impact on their longevity as well, but firstly their quality depends on used materials and manufacturing process. Due to years of development and innovation of scissors manufacturing, nowadays shears can be made from variety of different materials, but the most common materials which are used in production of scissors are explained below.
A long time ago cutlery makers knew that forging or, in other words, usage of compressive force in shaping of metal creates a material which stays sharper for longer time. Centuries ago they were pounding the sword with hammers to drive molecules more closely together, but today cutlery is drop forged with huge weight, being dropped onto the mold to pound the steel into desired shape. Before forging the steel is heated to about 1200F, but after forging the steel is put into a bath of cold liquid to harden the steel. Sometimes this process is called “ice tempering”. Ice tempering leaves the steel compressed, providing durability and longevity.
Another way to give a blade its shape is casting. Casting of metal includes metal heating to a liquid form which is around 2500F. When it is done, liquid metal is poured into a mold. When the metal cools in the mold, it expands, leaving molecules much more widely separated and making the metal more brittle, therefore, cast shears do not stay sharp as long as mentioned forged shears.
Unfortunately, it is almost impossible to know cast shears from forged shears by sight, as well as it may be difficult to get reliable answer from salesman, because they often do not know the true answer. The majority of shears from China and Taiwan are cast, but many shears are not marked with the originating country. Everything what the customer can do is to deal with reliable manufacturers in order to get warranty of their production.
Most of shears are made from some sort of alloy. Usually alloys are made, combining at least two or more metallic elements to improve strength and resistance to corrosion, as well as to add some other, special features. Nowadays it is not a secret that longevity, sharpness and resistance against damages of shears can be enhanced with the base material of alloy and those it is combined with. Nickel is added to almost all alloys to add sheen to the material and improve resistance against corrosion, but unfortunately nickel is a material which causes allergies to many people, making it impossible to work with shears which contain nickel.
Stainless steel alloy
One of the most common and popular alloy which is used in manufacturing of scissors is stainless steel. The two main types of stainless steel which are used in hairdressing industry are 440C and 420A stainless steel. It is not a secret anymore that the best stainless steel materials are those which are made in Japan and Germany, because both of these countries have long history of cutlery making, as well as both of them have focused on creating very refined steel for this purpose. Comparing 440C and 420A stainless steels, 440C material is better, because it contains higher amount of carbon, as well as can be tempered to get even higher hardness.
Cobalt base alloy
Cobalt base alloy is another material which is extremely popular among today’s manufacturers of shears. Cobalt is known with its ultimate resistance against rust and chemical resistance, but it also can nick and chip easily, therefore, the blades become non-adjustable after multiple sharpening. Despite the fact that cobalt alloy shears wear out sooner than, for example, stainless steel shears, they cost more than stainless steel scissors.
Molybdenum alloy is an ideal material, comparing it to stainless steel or cobalt alloy. It can be hardened to a high level, without becoming brittle because of flexibility of molybdenum. Thanks to its properties, shears which are made of molybdenum alloy have fine and razor-sharp edge which lasts for long time.
Cobalt molybdenum base alloy
In order to get non-brittle and non-fragile shears which also have chemical and rust resistance, molybdenum is added to a cobalt base alloy. As mentioned before, cobalt has chemical and rust resistance, but molybdenum has flexibility.
Sintered steel and carbide steel
There are some exotic materials which are used in some of today’s most expensive hair cutting shears as well. For example, sintered or, in other words, powdered steel is extremely hard, but unfortunately it can be brittle and hard to sharpen too. Other material is carbide steel which is perfect at edge retention. Hair cutting scissors which are made of these special materials have quite high prices, because it is extremely difficult to make qualitative shears from these materials.
Titan or titanium coating
Covering shears with titanium coat is the way how to add a special color to shears. It should be mentioned, that titanium coat has no positive or negative effect on the edge retention, because it is not covered on the edge of scissors. Actually it is usually done to make inexpensive shears appear more attractive and thus expensive. It is important to mention, that titanium coated shears may be appropriate and good for those who have nickel allergy.