75Cr1:It is a low alloy tool steel, almost a carbon steel. It contains trace amounts of Chrome, which is irrelevant for corrosion protection and ~.75% carbon. It is easily machined, and very tough even at a hardness of ~59Hrc, while it tolerates fine and acute edge angles. The blade can be easily resharpened; however, it has good edge retention. When used regularly, the blade will need maintenance.
(C:~.75%, Cr:~.35%, Mn:~.7%, Si:~.4%)
100Cr6 (GO3): It is also a low alloy tool steel. It is widely used for rolling bearings. It has a relatively high carbon content (hipereutectoid), which provides very good edge retention characteristics. It contains trace amounts of chrome, irrelevant for corrosion protection. (the amount present serves to increase through-hardening diameter, thus it is oil-hardened). Like every low alloy steel it allows drawing a fine edge and it tolerates acute edge angles relatively well.
(C:~1%, Cr: ~1.5%, Mn:~.35%, Si:~.25%)
K510: This steel is produced by Böhler. It is also called “Silver Steel”. Its composition and application make it similar to 100Cr6, with a slightly tougher and finer edge.
(C:~1.1% Cr: ~.7%, Mn:~.3%, Si:~.2%, V:~.1)
Sleipner:Cold work tool steel manufactured by the Swedish company Uddeholm. While its 8% chrome content is not enough to provide absolute stainlessness, it makes for seamless everyday use and you may expect only rust spots even in corrosive environment. The steel has a carbon content typical of a eutectic system and also contains carbide-formative alloys (Mo and V), so it has near optimal charateristics to be used for making all purpose knives. It is very tough considering its being alloyed and tolerates acute edge angles well. It can be easily sharpened even manually and it retains the edge for a long time. Its edge retention property of course is not as good as that of stronger and harder alloys, but it is easy to sharpen and very user-friendly, which will surely make up for having to sharpen it more often.
(C:~.9%, Cr:~7.8%, Mn:~.5%, Si:~.9%, Mo:~2.5%, V:~.5%)
K110 (D2): This cold work tool steel is produced by Böhler and has been available on the market for a very long time. Used for high-duty tools where excellent wear resistance is required. It is rather difficult to machine. Its 12-13% chrome content may appear to be high, but its also high carbon content (ledeburite structure with a carbon content of ~1.55% ) does not allow absolute stainlessness. More visible stains, however, do not usually appear on the surface; micropits are more likely to form. During everyday use its stainlessness property is slightly better than that of Sleipner. Thanks to its high carbon content and a little amount of carbide-formative alloys, this steel has excellent wear resistance, therefore it has very good (one of the best) edge retention property. On the other hand, sharpening the blade can be a bit of a challenge. Due to the relatively large grain size and brittleness, it does not tolerate well the fine and acute edge angles. Also, its resistance to breaking must be taken into account, especially in the case of larger blades.
(C:~1.55%, Cr:~11.3%, Mn:~.3%, Mo:~.75%, V:~.75%)
4034 (~Ko13): One of the most widely used types of stainless steel worldwide. It has several areas of application: it is used to manufacture medical device parts, food industry installations, springs, cutter knives. It has a chrome content of ~13-15% and a relatively low carbon content ( ~.45%), and it contains no other carbide-formative alloys. It can be hardened to 55-57 Hrc. At this hardness it features outstanding toughness and sharpenability. However, its edge retention property is not the best. It is most suitable for applications where stainlessness, easy sharpenability and toughness are of crucial importance.
(C:~.45%, Cr:~13%, Mn:~.4%)
4116: This steel has a carbon and chromium content similar to the previous one. However, it contains carbide-formative alloys (M and V) which provide better properties. Especially its edge retention properties are better than those of the previous material. While its sharpenability is pretty much the same, it can be honed easier. Thanks to the carbide-formative alloys, knives made of this steel have a slightly finer edge than 1.4034 steel knives. No wonder it is a popular choice for quality kitchen knives and pocket knives and fix-blade knives designed for everday use.
(C:~.5%, Cr:~14.5%, Mo:~.65%, Si:~.4%, V:~.15%)
N695 (440C) : This is a corrosion resistant tool steel produced by Böhler. It was developed for ball bearings (mostly for the ball bearings used on oil rigs). It has a high carbon (~1%) and chromium (~17%) content, but is not very rich in carbide-formative alloys (it has a small amount of Mo). It is hard to machine and has very good wear resistance almost reaching that of D2. It is slightly harder than D2 and can be sharpened somewhat easier, but it does not tolerate well very acute and fine edge angles. Widely used for hunting knives and knives for everyday use.
(C:~1.05%, Cr:~16.7%, Mn:~.4%, Mo:~.5%)
N690 (VG10):Also a product of Böhler. (Its alloy content and application areas are basically identical with that of the Japanese VG10). Its carbon and chromium content is similar to N695, but it contains more carbide-formative alloys (Mo and V) and cobalt (which provides a good base for the embedding of carbides and improves heat conduction properties). It machines rather hard. Its properties and application areas make it similar to N695, but its edge retention is better, it allows drawing a finer edge and better tolerates bigger blade length.
(C:~1.08%, Cr:~17.3%, Mn:~.4%, Si:~.4%, Mo:~1.1%, V:~.1%)
Elmax: It is a Swedish powder metallurgical steel, manufactured by Uddeholm. It machines very hard due to its high alloy content. It is used for knives with the best edge retention, but its sharpenability properties are rather poor. It also has satisfying toughness. However, its production technology gives this steel fine carbide distribution and allows fine edges. Like every highly alloyed steel, Elmax does not tolerate acute edge angles, although it tolerates medium edge angles. It is used to manufacture exclusive hunting knives and everyday use knives with not very long blades.
(C:~1.7%, Cr:~18%, Mn:~.3%, Si:~.8%, Mo:~1%, V:~3%)
Rwl-34: It is also a Swedish powder metallurgical steel, manufactured by Damasteel. It has been used for long as raw material for exclusive knives. It is a highly alloyed (though not as highly as Elmax) steel. Its carbon content is lower than that of Elmax. It is easier to machine and to polish. Its application and properties are similar to those of Elmax, but it is tougher, more resistant to breaking and easier to sharpen. However, its edge retention values are somewhat lower. Thanks to these properties, it is more widely used than Elmax.
(C:~1.05%, Cr:~15%, Mn:~.5%, Si:~.5%, Mo:~4%, V:~.2%)
Wrote: Imre Palcsesz