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A reasonable structural decomposition method is the foundation of studying the error propagation mechanism precisely. In this paper, a new Function-Motion-Action-Part (FMAP) structural decomposition method is proposed to analyze the mapping model between the geometric dimension of part and output errors of a mechanical product. First, the meta-action unit (MAU) theory is extended to the part layer, and the MAU structure and the MAU chain are redefined. Second, according to the coordination characteristics of the parts in MAU, the error expression model of the parts and the error propagation model of the MAU assembly process are established. The state-space model of the MAU output error is further established so as to complete the mapping model from the geometric dimension of manufactured parts to the precision of the MAU. Then, according to the characteristics of the kinematic error propagation between the MAUs, the input and output error indexes of the MAU chain are determined, and the error propagation model in the MAU chain is established based on the radial basis function network. Finally, the methodology is applied to a numerical control rotary table to verify the effectiveness of the FMAP structural decomposition method for the error propagation mechanism analysis.

Longitudinal ultrasonic vibration-assisted high-speed dry milling (LUVAHSDM) is performed to improve cutting performance and surface quality of Ti-6Al-4V (TC4). Multifaceted comparisons are presented in milling results of AlCrN, AlCrSiN, AlTiN and AlTiSiN-coated tools in terms of milling force, milling temperature, tool wear, 3D surface roughness and residual stress. The results show that maximum milling force in both the feed and longitudinal directions rst decreased and then increased with increasing Al element content as well as single edge and average ank wear. Therefore, the surface roughness of TC4 becomes more uniform when using AlTiN-coated tools, the residual stress is greatly reduced to 98.57 MPa. Combining milling force, milling temperature, tool wear, 3D surface roughness and residual stress data, it is found that AITiN-coated tools achieve both excellent cutting performance and surface quality. The excellent machining performance demonstrates the feasibility and effectiveness of applying LUVAHSDM methods.

A novel dopamine- and aluminum-doped zinc oxide (DAZO) sensing film was prepared by blending DAZO nanoparticles with silicone latex; this film has promising applications for the thermal runaway warning system of new energy batteries. The DAZO nanoparticles were generated by the coprecipitation–calcination method through the structure-orienting modification of eco-friendly polydopamine biomaterials, followed by the doping of aluminum and nitrogen into the zinc oxide lattice. Dopamine was used as a nitrogen source; it easily self-polymerizes to form polydopamine, which is then pyrolyzed and doped into the zinc oxide lattice. The negative temperature coefficient (NTC) effects of the DAZO film and the aluminum-doped zinc oxide (AZO) film below 150 °C were tested and compared. The results showed that the DAZO film had a more pronounced NTC effect than the AZO film because of the doped nitrogen element. DAZO films exhibited good recyclability and thermal stability during the high-low temperature NTC cycle test. X-ray diffraction, transmission electron microscopy, scanning electron microscopy, Fourier transform infrared spectroscopy, thermogravimetry/mass spectrometry (TG–MS), and energy dispersive X-ray spectroscopy were performed to characterize the fabrication of the synthesis mechanism of the DAZO nanoparticles. The NTC effects of DAZO films with varying aluminum doping amounts, varying dopamine doping amounts, and different pH values were investigated. Nitrogen doping in the conventional AZO nanoparticles enhanced the sensitivity and low-temperature NTC effect; this is because of the increase in the DAZO grain size due to doping and the structure–orientation of polydopamine, which further leads to the increase in the height of the grain boundary potential barrier. On the basis of the test results, an alarm response device at different temperatures was initially established, and its alarm response at different temperatures was simulated and tested, which showed the possibility of the application of the DAZO film to the runaway warning system for the new energy batteries.