RESEARCH OF THE MECHANISM OF COMPACTION OF MIXTURES OF POWDERS OF REFRACTORY CARBIDES WITH A METALLIC BOND IN EXPLOSIVE PRESSING ON A METAL SUBSTRATE

The results of investigations of the features of the behavior of the components of mixtures of refractory carbide powders with metals during explosive pressing are presented. It is shown that the main factor determining the compaction of mixtures is the dynamic flow of one of the phase components of the mixture into the initial pores of the powder. As the phase component of the mixture, the movement of which limits the degree of compaction and leads to the formation of a continuous matrix in the structure of the material pressed by the explosion, both the metal binder and the carbide component of the material can act.

Influence of the nano-WC content and Sintering Temperature on the Phase Composition of Hard Alloys in the System TiC–WC–VC–NiCr

The effect of the WC content and the sintering temperature, as the main technological factor, on the phase composition of TiC–xWC–5VC–18NiCr alloys was investigated by X-ray phase analysis. It was established that the main phases in the investigated alloys were the NaCl-type quaternary (Ti,V,W)C phase and a solid solution of Cr in Ni. Depending on the size of the WC particles used for the preparation, the metal binder could be described by the formula Ni0.75Cr0.25 (for nano WC) or Ni0.5Cr0.5 (for fine-sized WC). In alloys prepared with fine-sized WC, elementary Cr and traces of the Cr3C2 and Cr23C6 were also found. With increasing content of nano-sized WC and sintering temperature the solubility of W in (Ti,V)C increased. No W2C phase was detected under the conditions of the investigation.

RESEARCH OF THE MECHANISM OF SEALING POWDER MIXTURES BASED ON SILICON CARBIDE IN EXPLOSIVE PRESSING

The effects of the metal binder content and parameters of shock-wave compression on the compaction of SiC-Ti powder mixtures under explosive loading were investigated; microstructure of the obtained materials; The prevailing mechanisms of compaction of powder mixtures of silicon carbide with titanium during explosive pressing are revealed.

Metal Binder Jetting Additive Manufacturing: A Literature Review

Binder jetting is an additive manufacturing process utilizing a liquid-based binding agent to selectively join the material in a powder bed. It is capable of manufacturing complex-shaped parts from a variety of materials including metals, ceramics, and polymers. This paper provides a comprehensive review on currently available reports on metal binder jetting from both academia and industry. Critical factors and their effects in metal binder jetting are reviewed and divided into two categories, namely material-related factors and process-related parameters. The reported data on density, dimensional and geometric accuracy, and mechanical properties achieved by metal binder jetting are summarized. With parameter optimization and a suitable sintering process, ten materials have been proven to achieve a relative density of higher than 90%. Indepth discussion is provided regarding densification as a function of various attributes of powder packing, printing, and post-processing. A few grades of stainless steel obtained equivalent or superior mechanical properties compared to cold working. Although binder jetting has gained its popularity in the past several years, it has not been sufficiently studied compared with other metal additive manufacturing (AM) processes such as powder bed fusion and directed energy deposition. Some aspects that need further research include the understanding of powder spreading process, binder-powder interaction, and part shrinkage.