Investigation of the Influence of Direct Metal Deposition Modes on Microstructure and Formation of Defects in Samples of Heat Resistant Alloy

The article discusses the influence of technological modes of the DMD method on the macro- and microstructure of a heat-resistant nickel-based alloy to use this technology for heat-resistant materials in the manufacture of parts for combustion chambers in gas turbine plants.

Improving the Efficiency of Turning Processing of Heat-Resistant Alloys by Introducing Ultrasonic Field Energy into the Cutting Zone

Studies have been carried out to assess the effectiveness of dry processing by the current preparations from the heat-resistant alloy CN45MVTUBR with mineral ceramic incisors with the introduction of the ultrasound-field energy treatment zone. It has been established that the use of ULTRASOUND in the rough treatment of mineral ceramic tools without coolant allows to reduce the depth of the defective layer in 1.5 times.

The Effect of Vanadium Content Coupling with Heat Treatment Process on the Properties of Low-Vanadium Wear-Resistant Alloy

The development of wear-resistant materials with excellent properties is of great research value in the manufacturing industry. In this paper, a new kind of low-vanadium wear-resistant alloy was designed and characterized to unveil the influence of vanadium content coupling with heat treatment on the microstructure, hardness, and abrasive wear property. The performances of commercial high chromium cast iron (HCCI) and the new low-vanadium wear-resistant alloy are compared. The alloy with 3 wt.% vanadium quenched at 900 °C and tempered at 250 °C, possessing VC, Mo2C, and M7C3 distributed in the martensite matrix, displayed a wear resistance two times better than the HCCI. The results showed that the increase of vanadium content from 0.98 wt.% to 3.00 wt.% resulted in a decrease in the size of M7C3 and a more homogeneous distribution of M7C3. VC with a bimodal distribution is effective for impeding grooving or indenting by abrasives because of their high hardness, which plays a vital role in improving the wear resistance of low-vanadium wear-resistant alloy.

Magnetic Method for Rapid Detection of Carburization Degree of Fe-Cr-Ni Series High-Temperature Heat-Resistant Alloy

In view of the carburization of Fe-Cr-Ni high-temperature heat-resistant alloys in the ethylene cracking furnace and the hydrogen conversion furnace, this paper implemented the GMRI-I carburizing detector to test the degree of carburization of 25Cr35NiNb+ microalloy inlet pipe and 35Cr45NiNb+ microalloy outlet pipe of the ethylene cracking furnace after service as well as the reinforced joint made of Incoloy 800H from the hydrogen-making reformer. In conjunction with the results of the low-power acid corrosion test, a rapid detection method for the degree of carburization was proposed. Based on the experimental results of the carburizing detector and the laboratory test data, the carburization degree test curve of the above three alloys based on the magnetic field strength has been established. The detection accuracy was circa. 5% and the error was ±10%, which is convenient for guiding the use and replacement of Fe-Cr-Ni high-temperature heat-resistant alloy materials for ethylene cracking furnace and hydrogen conversion furnace, thereby ensuring the safe and stable operation of the device.

WEAR OF THE RIGHT KNIFE OF THE PSKU SPEED PLOW AND TECHNOLOGICAL MEASURES TO INCREASE ITS DURABILITY

The intensification of crop production has led to the creation of equipment for high-speed tillage. The high speed of plowing causes an increased intensity of wear of the working bodies of plows. The limit capacity of the vertical knife when processing loamy soils is about 30 hectares, after which the body must be subjected to repair (maintenance) operations. (Research purpose) The research purpose is in studying the wear of the right knives of the PSKU plow (geometry and location on the working surface), assessing the technical condition and develop measures to improve their durability. (Materials and methods) The right knife (plowshare) performs the function of a pruning element, its design corresponds to the design of the plowshare in the classic version, but with reduced dimensions. We carried out wear control in width and thickness on 14 parts. (Results and discussion) The knives after working 30 hectares are suitable for further use in width. The width of the solid layer deposited on the back side is about 7-8 millimeters, so additional surfacing of the abrasive-resistant alloy is necessary. The wear on the thickness of the knife cannot be the reason for its decommissioning, since the strength and rigidity are preserved, and the agrotechnical requirements for soil cultivation are not violated. (Conclusions) The residual width and thickness of the studied knives when plowing loam retain the normalized limits, which indicates the possibility of their further operation, but it is necessary to weld the cutting-blade part from the back with an abrasive- resistant alloy. The xiphoid wear is fused with an electrode that provides a roller hardness of about 50 HRC. A low level of wear rate of the part is achieved due to the hardness of the blade area 60 HRC.