With both methods, after shaping, the steel must be heat treated.
Knives are sharpened in various ways. Flat ground blades have a profile that tapers from the thick spine to the sharp edge in a straight or convex line. Seen in cross section, the blade would form a long, thin triangle, or where the taper does not extend to the back of the blade, a long thin rectangle with one peaked side. Hollow ground blades have concave, beveled edges. The resulting blade has a thinner edge, so it may have better cutting ability for shallow cuts, but it is lighter and less durable than flat ground blades and will tend to bind in deep cuts. Serrated blade knives have a wavy, scalloped or saw-like blade. Serrated blades are more well suited for tasks that require aggressive 'sawing' motions, whereas plain edge blades are better suited for tasks that require push-through cuts (e.g., shaving, chopping, slicing).This involves heating the steel above its critical point, then quenching the blade to harden it. After hardening, the blade is tempered to remove stresses and make the blade tougher. A fixed blade knife, sometimes called a sheath knife, does not fold or slide, and is typically stronger due to the tang, the extension of the blade into the handle, and lack of moving parts.
Modern fixed blade knives consist of a blade and a handle.
The blade consists of:
The point – the end of the knife used for piercing;
The edge – the cutting surface of the knife extending from the point to the heel can be plain or serrated or a combination of both;
The grind - the cross section shape of the blade;
The spine – the thickest section of the blade;
The fuller - the groove added to lighten the blade;
The ricasso - the flat section of the blade located at the junction of the blade and the knife's bolster or guard;
The guard - the barrier between the blade and the handle which prevents the hand from slipping forward onto the blade
The end of the handle, or butt.
A choil - where the blade is unsharpened and possibly indented as it meets the handle, may be used to prevent scratches to the handle when sharpening or as a forward-finger grip.
Single edged knives may utilize a reverse edge or false edge, in which the forward section of the knife's spine (opposing the sharpened edge) is thinned and left unsharpened.
The handle can include a bolster, which is a piece of material used to balance the knife, usually brass or other metal, at the front of the handle where it meets the blade. The knife's handle or butt may allow a
lanyard to be used to secure the knife to the wrist, or a portion of the tang to protrude as a striking surface for hitting or glass breaking.