Zincate treatment is a specific and mandatory pretreatment for depositing electroplated coatings on aluminum substrates despite its complex sequence. Fine particle peening (FPP) is proposed as an alternative simpler pretreatment to aid in coating of aluminum substrates. FPP using metallic shot particles enriched aluminum alloy substrates with elements transferred from the particles. Nickel coating was successfully deposited on the FPP-treated substrate, suggesting that FPP supported nickel electroplating. Interfacial adhesion between the coating and the substrate pretreated under varied FPP conditions was assessed and compared by bending test, which is a common method used to evaluate adhesion of electroplated coatings. The results indicated that the coating adhesion was affected by shot particle material to be transferred. Copper and iron transferred by FPP were effective in improving adhesion of Ni.

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Advancements in the motion of machine tools involving a five-axis-controlled machining center (5MC) and a multi-functional turning center have helped to achieve both high speed and high precision. Especially, the simultaneous motion accuracy of three axes at very high feed speed has increased markedly. However, it has become difficult to create female threads using a tapping process due to the use of difficult-to-cut materials. Therefore, we propose a processing technology for creating female threads in difficult-to-cut materials that utilizes both a thread mill tool and helical interpolation motion based on numerical control (NC) with a machining center. Here, we achieved screw cutting using three-axis motion control helical interpolation with a machining center. We examined the chatter vibration caused by threading machining by specifying the piezoelectric dynamometer and the wireless holder that can measure acceleration in the twisting direction.

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