A metalloceramic NiCrBSiFe−WC coating on structural steel 40Kh was prepared by the method of laser cladding. The cladding was performed using a multichannel continuous СО 2 laser radiation using the complex of ALTKU3 model produced by LLC "Centre of laser technologies", the city of Vladimir. The complex includes a multichannel (40 rays) СО 2 laser with the output power of 3 kW and a technological stand with five coordinates for ray manipulation and with two ones for manipulation of the piece under processing. The prepared samples were examined metallographically. It is shown that at optimal modes a practically pore-free coating is formed with a minimal penetration into the base ensuring metallurgical fusion. According to the X-ray spectral microanalysis data the chemical composition is practically the same as that of the raw powder. In particular, the content of iron in the granules and in the matrix is nearly the same (about 4…5 %). Due to the automatization of the processing by crossed rollers the sample surface after cladding is nearly flat and only requires a slight machining. The thickness of the cladding layer is about 700 μm in one pass. No cracks in the plane of the sample were observed. The weld junction demonstrates the same structure lengthwise thus indicating a high uniformity of the heat input during the cladding. The size of the thermal effect zone in the substrate is about 450 μm. The laser cladding of the highly alloyed powder of the system NiCrBSiFe−WC onto the structural steel by means of the multichannel СО 2 laser makes it possible to obtain a high-quality wear-proof coating since, in contrast to single ray lasers, it provides a high uniformity of integral heat input in the processing zone.
The performance characteristics of linear Hall element sensors for non-contact determination of the position of a moveable permanent magnet along a pre-established path are analysed. Simple theoretical expressions suitable for computer modelling of previously described sensors are presented. Practical measurements have verified the theoretical predictions arrived at by simulation means. Having established the validity of the basic formulae predictions of performance for a variety of magnet configurations can now be attempted using superposition principles. As an application, a method of improving the linearity of a simple sensor with a single cylinder magnet by means of shaping the cylinder to a special profile is described. An altemative example is a new high-gradient configuration of a radially symmetric sensor construction on a base of two oppositely magnetized rings.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.