| Ti(C,N) based cermet has been more and more popular with thescholars at home and abroad because of its high hardness, wear resistanceand good red hardness, thermal conductivity and chemical stability andthe ability to resist adhesive, etc.in recent years. It is true that Ti(C,N)based cermet is a potential tool material. The author of this paper usedthe new rapid sintering method-microwave sintering technology toprepare the Ti (C, N) based cermet samples and Ti (C, N) based cermetsamples with adding the grain inhibitor VC. In addition, the author usedordinary lathe (model CA6140) to test sample cutting tools for cuttingafter sintering. At the same time, the conventional sintering test has beencompared with the microwave sintering. This paper mainly discussed theimpacts of sintering temperature, holding time and the content of graininhibitor VC on the micro-structure and mechanical properties of thesamples after microwave sintering. And the scanning electron microscope(SEM with EDS) has been used to observe and analysis the raw materialpowder morphology, fracture morphology and pore distribution of Ti(C,N) based cermet. Moreover, the40times tool microscope has been usedto observe the tool wear state of the samples. The main conclusions wereas follows:1. The Ti(C, N) based cermet with fine grain size, well-closedformation and excellent performance can be prepared by microwavesintering technology. The density, bending strength and hardness of Ti (C,N) based cermet are gradually increasing with the increasing sinteringtemperature at the first place, but then suddenly fall, there was amaximum at1450℃.And the density, bending strength and hardness areincreasing with the increase of holding time at the first place. decreases,there was a maximum in30min.Therefore, the suitable sintering processof microwave sintering Ti (C, N) based cermet is sintering at1450℃for holding30min.2. Comparing with the conventional sintering-integration technologywith the vacuum dewaxing-sintering system, Microwave sintering canenhance its density, bending strength and hardness. The bending strength and hardness value were1240MPa and91.6HRA respectively.Compared with the conventional sintering, them have increased by1.8%and14.50%respectively.3. The author used the microwave sintering technology to preparethe Ti(C, N) based cermet with adding the grain growth inhibitor VC.The results showed that it got smaller grains, more homogeneousstructure and more excellent performance of Ti (C, N) based cermet bythe microwave and inhibitors of VC. With the increase of VC, the density,bending strength of Ti(C, N) based cermet firstly increases then decreases.When the grain growth inhibitor VC content was0.75wt.%, the flexuralstrength and hardness of sintered sample got1243MPa and92HRArespectively, and the grains of the sample was the smallest and theorganization structure became the most homogeneous. The resultsshowed that the sintered sample of Ti(C, N) based cermet byconventional sintering presented a best bending strength and hardnesswhen the grain growth inhibitor VC content is0.75wt%, But the overallmechanical properties were not good compared with microwavesintering.4. The cutting test results of sample tools sintered by this twotechnology were analyzed. It can be found that the overall mechanicalperformance of Ti(C, N) based cermet sample cutter by microwavesintering method under the condition of the cutting value VCwas200m/min, f was0.1mm/r,apwas0.5mm was superior to the samplecutting tools by conventional sintering. The Ti(C, N)based cermet samplecutting tool designed according to No.2cermet components(adding0.75wt%inhibitor VC) kept a better performance than the sample cutterdesigned according to No.1cermet components (without adding inhibitorVC).5. The microscopic observation of the sample cutter was made.There were lots of attachments found near the tip. Energy spectrumanalysis of these attachments was made to discover that the90percentsabove atomic percentage is composed of Fe and O. |
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