Apex Ultra

The ApexUltra is a newly developed knife steel that is particularly suitable for the production of blades with the finest cutting edges, which at the same time should be highly wear-resistant. The steel has a very well thought-out alloy composition and was also manufactured using the ESR process. As a result, the steel has a very homogeneous distribution of the alloying elements, a very small amount of gas and foreign body inclusions and a very low content of steel pests. In addition, the steel was rolled from the slab to the flat material (not just to the sheet), which also favors the fine distribution of the alloying elements. These are the basic requirements for top performance.  

The American metallurgist Larrin Thomas, the Austrian metallurgist and knife smith Tobias Hangler and the Swiss chef and kitchen knife smith Marco Guldimann worked together on the development of this high-quality steel. The aim was to develop a steel that has a very high level of hardness and wear resistance that can be achieved, but at the same time offers such high toughness that it is suitable for the finest cutting edges and acute grinding angles.  

The data sheet and further information about this interesting steel can be found directly on the ApexUltra website.

But here I would like to share my personal experiences with the ApexUltra:

- First of all, I would like to point out that although the steel is extremely homogeneous, the carbides are not necessarily as small as possible when delivered. The same applies to the austenite grain, which can certainly be classified as very good, but does not have the highest possible fineness. When delivered, the steel is already above average. However, in order to get the maximum performance from the steel, the steel can/should be normalized and fine-grain annealed according to the specifications in the data sheet.  

- In order to achieve full performance and the hardness and toughness values ​​specified in the data sheet, the heat treatment should be carried out exactly according to the specifications in the data sheet. Only for fine-grain annealing has a holding time (the time after the blade has been completely heated through) of 3-4 minutes proved to be sufficient. For fine grain annealing, I recommend three cycles.  

- In the area of ​​"medium use sharpness" I find the wear resistance of the ApexUltra to be comparable to 1.2562. With very thinly ground blades, acute grinding angles and high sharpness (>5k grit), on the other hand, I find the ApexUltra to be clearly superior. Here, the Apex offers much better cutting edge stability and even with hardness values ​​beyond 65hrc and acute grinding angles, the tendency to microchipping is much lower than with 1.2562.  

- Interestingly, the ApexUltra is easier to finish than the 1.2562. This can be attributed to the smaller and more finely distributed carbides.

- When hardening, it is essential to carry out a deep-freeze treatment. The simplest method is freezing with dry ice (-78 °C). 3mm dry ice pellets have proven to be optimal. These can be ordered from numerous retailers on the Internet. Immediately after quenching, once the blade has reached room temperature, it is placed in dry ice and completely covered for 30-45 minutes. Attention, large amounts of carbon dioxide are produced when dry ice evaporates. The gas is heavier than air and can completely flood rooms, basements, garages, cars, etc. Many people have lost their lives due to improper use of dry ice. Under no circumstances should dry ice be used or stored in closed rooms or transported in a car. It is best to store and use dry ice outdoors only.  

The steel is currently available in 5.2x50mm and 5.2x120mm. Other dimensions will be available after Easter