X46 – Stainless Steel Linear Shafts (WRB) – Induction Hardened Linear Shafts

The X46 Stainless Steel Linear Shaft is a very similar material to the X90 Stainless Steel Linear Shaft (WRA) type, but with a different chemical composition due to the reduced chromium, vanadium and molybdenum content. This in turn means the X46 does have a reduced chemical resistance to corrosion, but can be a more cost-effective alternative to the X90.

In an X90 Stainless Steel linear shaft, there is approximately 17-19% Chromium content which gives the shafts their excellent corrosive resistance, along with 0.9-1.3% Molybdenum which gives the material its strength, hardness and durability. The X90 also has 0.07-1.2% Vanadium to give the material its toughness, as well as shock and vibration resistant properties. At first glance, the X46 may appear just the same as any other linear shafts but the metallurgical differences are important to note as the X46 contains these chemical elements but in smaller quantities so, though the X46 does has similar properties to the x90, they are not quite the same.

Nevertheless, the X46 is still a good alternative where resistance to corrosion is paramount and the linear shafts are subjected to a stringent process during production to ensure excessive internal stresses are prevented. Therefore, with excellent hardening properties and high grinding finish it is often selected to be used in high-quality, linear bearing and guideway systems, where corrosive resistance and induction hardened materials are needed.

Indeed, the manufacturing process is where linear shafts gain their significant performance differences over other steel bars. Firstly, the linear shafts go through a process called induction hardening, which involves induction heating, followed by quenching. During these processes, the linear shafts are heated up before rapidly cooling them back down again which, as a result of this process, both hardens the linear shafts but also increases their brittleness. This means any subsequent machining operations, such as milled flats, radial and axial drilling and tapping, turned-down diameters and keyways and planes – as well as, of course, cutting the bars when breaking through the “induction hardened skin” – requires engineers with significant experience and expertise to do so.

Furthermore, the linear inner race demands the highest levels of taper and roundness, material cleanliness and straightness, diameter, surface topography, surface hardening and surface finish to ensure the X46 Stainless Steel Linear Shafts provide optimum performance, at minimal wear and maintenance, to ensure they last for the long periods of time required for the application they serve.

Our X46 materials are used in a number of highly specialised applications, especially ones where any possibility of corrosion needs to be minimised.

• Special tolerances and diameters are available upon request.
• Length tolerance: +200 / -0mm.
• Surface hardness: 53 HRC min.