What is stainless steel?
Why is stainless steel corrosion resistant?
Can rust occur in stainless steel?
How can extraneous rust be prevented?
How many different types of stainless steel are available?
How are stainless steels categorized?
What is the difference between these groups?
Which stainless steel does Wera use?
What hardness scale is used to measure the hardness of stainless steel?
Is stainless steel softer than the carbon steel used in "regular" hand tools?
Are stainless tools suitable for the shop floor?
Why is there a need for stainless steel fastening tools?
What about stainless steel and magnetism?
What is the cost difference between stainless steel and carbon steel?
Are stainless hand tools cost effective?
Are stainless steel hand tools compatible with my stainless steel process equipment?
How should I store stainless steel hand tools?
What is passivation?
What is INOX?
Can I autoclave Wera Stainless Steel drivers, hex keys and bits?

What is stainless steel?
Stainless steel is a range of alloys. Elements of these alloys are chromium, nickel, iron, manganese, silicon, phosphorous, copper, molybdenum, titanium, columbium, and tantalum. When the proportions are changed, the characteristics of the resultant alloy change.

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Why is stainless steel corrosion resistant?
Stainless steel is a low carbon steel that contains 10% or more chromium by weight. Chromium gives the steel its anti-corrosion property by allowing the formulation of an invisible chromium-oxide film on its surface. When it comes into contact with oxygen, even in small quantities, this film self-repairs if damaged mechanically or chemically. The corrosion resistance of stainless steel is enhanced by increasing chromium content and the addition of other elements such as molybdenum, nickel and nitrogen.

Can rust occur in stainless steel?
Yes. Stainless steel is corrosion-resistant, but extraneous rust can occur if the material is handled incorrectly. The results are visual damage and functional loss, even pitting corrosion. In this way, the advantages of stainless steel are lost. Extraneous rust is caused by using tools made from conventional steel on stainless steel fasteners. Even the hardest tools produce debris that leaves steel particles on the stainless steel surface. These particles turn to rust when exposed to oxygen.

How can extraneous rust be prevented?
Using stainless steel tools is the only way of preventing extraneous rust.

How many different types of stainless steel are available?
Because of the nearly unlimited number of combinations of elements within stainless steel, the number of different types is almost limitless.

How are stainless steels categorized?
Stainless steels can be found in four different categories: Austenitic (300 series), Martensitic (400 series, which Wera uses), Precipitation Hardenable (17-4PH, 455), and Ferritic (430, 443).

What is the difference between these groups?
The main difference lies in the type of hardening.

Which stainless steel does Wera use?
Wera uses high carbon matensitic steel to reach the required hardness for perfect tool properties. We do this by using a special heat treatment and a cryogenic tempering process.

What hardness scale is used to measure the hardness of stainless steel?
That is the Rockwell "C" scale; it is abbreviated to "HRC".

Is stainless steel softer than the carbon steel used in "regular" hand tools?
In general, yes. But Wera's proprietary hardening technology results in a 100% shop floor-proof hardness. Wera Stainless Steel tools are hardened in a vacum-ice atmosphere.

Are stainless tools suitable for the shop floor?
Wera has developed a special production process to ensure that Kraftform Stainless Steel tools meet the same hardness requirements as conventional tools. The tools are vacuum ice-hardened to give them the hardness required for industrial applications.

Why is there a need for stainless steel fastening tools?
There is an increasing demand for stainless steel products, such as windows and doors, sinks and fittings, balconies and patios, fences and facades. These and other products require stainless steel fasteners, and using stainless steel tools on the fasteners reduces the risk of unsightly rust.

What about stainless steel and magnetism?
Each alloy shows different magnetic characteristics. Only the Austenitic (304, 316, 316L) stainless steels are non-magnetic. All other alloys, including the one that Wera uses, are magnetic to some degree.

What is the cost difference between stainless steel and carbon steel?
Carbon steel is normally one-tenth the cost of stainless steel. Wera's stainless steel tools, however, are economically priced. Contact your Wera authorized distributor for pricing.

Are stainless steel hand tools cost effective?
Wera has priced our stainless steel hand tools in such a way that every professional can afford them. Durable stainless steel tools can reduce the cost of tool replacement, and costs associated with ferrous contamination.

Are stainless steel hand tools compatible with my stainless steel process equipment?
Yes. Stainless steel hand tools are entirely compatible with stainless steel process equipment.

How should I store stainless steel hand tools?
Stainless steel hand tools should be stored separately from carbon steel hand tools and containers. Autoclaveable plastic trays can be used, for example. If stainless steel tools come into contact with carbon steel, extraneous rust contamination can occur, and passivation may be necessary.

What is passivation?
Passivation is the removal of iron particles from the surface of stainless steel. The removal of iron particles facilitates the interaction of the chromium in the steel with oxygen which produces the formation of the passive, oxide film layer. This thin and invisible layer protects material from further corrosion by its ability to self-repair. If the material is scratched and the passive film disrupted, more oxide will form and cover the exposed surface. For deep scratches, material can be passivated again.

What is INOX?
Inox is another name for stainless steel.

Can I autoclave Wera Stainless Steel drivers, hex keys and bits?
Yes, Wera Stainless Steel tools can be autoclaved to sterilize them, up to 110º C (230º F), under normal conditions. Autoclaving processes vary widely. Customers should first test a Wera Kraftform Stainless Steel screwdriver in their autoclave. If they have any concerns they can send it afterwards to Wera for examination. Contact your Wera representative for more information.