In the section "Choosing the Right Knife," we give you all the basic information
you need to help with your selection of a knife. Here, in Technical Data, we get
into some more advanced information.
Knife Terminology
Steel Specifics
Making of a Knife
Heat-Treating
Knife Terminology
A knife blade may look simple, but there's a lot that goes into the making of a
quality blade that will have the strength and edge-retention that ensures
consistent, reliable performance for years. Here's a useful compilation of the
terminology used to describe the properties that must be considered.
Alloy Steel - Steel that has been enhanced with additional elements (chromium,
molybdenum, vanadium, nickel) is called alloy steel.
Carbon - An element present in all steels. Increasing the carbon content
increases hardness.
Chromium - A major element in martensitic stainless steel that improves
hardenability, wear resistance and corrosion resistance.
Coils - Long steel strips that come in large rolls, which are fed into Buck's
fine blanking press as the first step toward making a blade.
Corrosion Resistance - A blade's ability to resist rusting which is the result
of exposure to the environment or elements.
Ductility - The blade's ability to flex, bend or take an impact without
fracturing. If the amount of flex or bend is small before cracking or breaking,
the blade is considered brittle.
Edge Retention - A measure of the blade's ability to hold an edge by resisting
abrasion and wear. The most objective test is the CATRA machine, a
computer-controlled testing machine that gives accurate and repeatable data for
an objective evaluation of edge sharpness and consistency.
Fine Blanking - Buck's advanced blade blanking system. Our fine blanking machine
is used to press a knife blade out of a coil of steel using a specifically
shaped die. Fine blanking produces consistently accurate parts that require
little additional machining.
Hardenability - The steel's ability to be hardened.
Hardness - A good indicator of steel's ability to hold an edge. A blade's
hardness is measured on the Rockwell "C" scale, a testing process described in
Making a Knife.
Heat-Treat - An important series of steps in developing blade properties, such
as toughness. For more information, please go to Heat-Treating.
Laser Cutting - Large blades and "hard steel" blades are cut from sheets of
steel on a state-of-the-art computer-controlled laser machine that has the
capacity to "laser out" blades to a specified shape.
Manufacturability - The ease in which steel can be machined, blanked, ground and
heat-treated.
Martensitic - Steels capable of being brought to a very hard condition are
called martensitic steels. This type is best suited for knife blades. See
Heat-Treating for more explanation.
Molybdenum - An element added to steel to improve hardenability, tensile
strength and resistance to corrosion and pitting.
Nickel - An alloy addition that improves steel's toughness, hardenability and
corrosion resistance. Nickel is a major element in steel used for kitchen
cutlery and dive knives.
Plate - Flat sheets of steel that are turned into knife blades by laser cutting.
Properties - Refers to such things as hardenability, ductility and toughness,
which are established by the particular chemistry of the steel and the proper
heat-treat process. Properties most important to knife blades are covered in
this glossary.
Rockwell - A hardness-testing machine that forces a small penetrator into the
surface. The depth of penetration correlates to a scale reading, the scale
normally used for knife blades is the "C" scale written as "Rc". The higher the
number, the harder the steel. Most blade steels are in the range of Rc 58-61. C
scale (Rc Buck maintains an Rc 58 on our standard steel. Our higher end steels
range from 59-61, depending on use.
Initial Sharpness - The sharpness of the blade "out of the box," and the
sharpness that is the goal when re-sharpening.
Stainless Steel - The common term "stainless" is misleading. More accurately, it
should be called "stain less" because it is not "stain free." In certain
environments, any steel with carbon will rust. Stainless steel's
corrosion-resistant properties make it a good material for knife blades.
Strength - Steel's ability to resist applied forces.
Tempering - The final step in the heat-treat process to improve toughness.
Tensile Strength - Ability to resist breaking. Ultimate Tensile Strength is the
maximum load per square inch a blade can sustain before breaking.
Toughness - A blade's ability to absorb energy by impact prior to fracturing.
Vanadium - A material added to steel to improve hardenability and promote fine
grain, an important factor in wear resistance.