Precision parts with complicated microstructures have been in increasing demand in the field of inertial navigation
systems and structured molds. Micro milling is a direct operation to manufacture the micro structure but it will induce
unexpected tool marks and deterioration layer. A novel lapping method based on controlled force is proposed as the final
finishing process. The method offers efficient position determination strategy for the structure and is capable to monitor
the lapping condition. In the paper, processing method and the developed lapping apparatus was firstly introduced. Then,
the individual influence on finished surface of several processing parameters including abrasive size, amount of feed and
lapping trajectory are investigated. Results show that the deterioration layer was successfully removed with different
slurries without diminution of its original form accuracy. Lapping efficiency is also taken into account in the choosing of
parameters. The formative mechanism of parallel scratches observed in experiments is analyzed and verified.
In the processing technology of optical microstructure, mechanical processing with high efficiency and quality is still
dominating. However, with microstructure surface quality higher and higher, the precision and ultra precision cutting
technology has been difficult to meet the needs of reality, and it still remains a big issue in production efficiency and
cost. In this case, the elliptical vibration cutting method is created. At present, research on the effect of elliptical
vibration cutting on surface quality of microstructures with special optical properties such as V-groove, micro pyramid
and sinusoidal grid surface is rarely seen. This paper focuses on the elliptical vibration cutting process of arc groove and
V-groove, aiming at finding the discipline of various parameters (frequency, amplitude, feed rate) and analyzing the
surface quality through experiments. Firstly, the principle of elliptical vibration cutting is introduced, the cutting
mechanism and the theoretical error are analyzed, and a vibration cutting system is designed for precision machining.
Because the surface quality and burr play have a huge impact on optical microstructure, effects of the vibration
frequency (0-2kHz), amplitude (0.5-2.5μm) as well as feed rate (6-30mm/min) on surface quality and burr suppression
are analyzed. The experimental results show that compared to normal cutting, elliptical vibration cutting has obvious
advantages. With the increases of the frequency and amplitude, the surface quality improves significantly, the surface
roughness is changed from 61.5nm to 25.3nm, and burr has been suppressed to some extent.
An ultra-precision machine tool for machining of the roller has been designed and assembled, and due to the obvious impact which dynamic characteristic of machine tool has on the quality of microstructures on the roller surface, the dynamic characteristic of the existing machine tool is analyzed in this paper, so is the influence of circumstance that a large scale and slender roller is fixed in the machine on dynamic characteristic of the machine tool. At first, finite element model of the machine tool is built and simplified, and based on that, the paper carries on with the finite element mode analysis and gets the natural frequency and shaking type of four steps of the machine tool. According to the above model analysis results, the weak stiffness systems of machine tool can be further improved and the reasonable bandwidth of control system of the machine tool can be designed. In the end, considering the shock which is caused by Z axis as a result of fast positioning frequently to feeding system and cutting tool, transient analysis is conducted by means of ANSYS analysis in this paper. Based on the results of transient analysis, the vibration regularity of key components of machine tool and its impact on cutting process are explored respectively.
Precision micro-milling technology is an important method to machine microstructure. However, precision micro-milling
cutting system has relatively low stiffness. This will directly lead to the deterioration of the machining quality and thus
cannot fulfill the high accuracy requirements of parts. Vibration assisted machining has produced a good effect in high
stiffness cutting system using non-rotary tool. In this paper, the workpiece vibration assisted method is adopted instead,
to improve the processing condition and the practical machining quality.The vibration assisted system is a vibration
worktable driven by a piezoelectric ceramic actuator. In order to study the influence of vibration frequency on the
machining quality, a non-resonant vibration assisted worktable is designed to realize the adjustment of vibration
frequency. Orthogonal experiment is conducted to study the influence of three factors including the feed rate, vibration
frequency and amplitude on the machining quality. The ranges of these factors are 1 μm/z to 5 μm/z, 500 Hz to 4000 Hz,
and 0.5 μm to 2 μm, respectively. The experimental results show that, in the extent of the process parameters, form error
(P-V value) and roughness (Ra) decrease as the vibration frequency increases, while the vibration amplitude contributes
to good surface quality only in a proper range. Too low amplitude has little influence on the machining quality, and too
high amplitude may even worsen the quality. And after the vibration assisted method is applied, the PV value and Ra can
be reduced by approximately 27% and 42%.