Shengtao Lin and Zhengcai Zhao
Complex and exquisite patterns are sculpted on the surface to beautify the parts. Due to the thin-walled nature, the blank of the part is often deformed by the forming and…
Abstract
Purpose
Complex and exquisite patterns are sculpted on the surface to beautify the parts. Due to the thin-walled nature, the blank of the part is often deformed by the forming and clamping processes, disabling the nominal numerical control (NC) sculpting programs. To address this problem, a fast adaptive sculpting method of the complex surface is proposed.
Design/methodology/approach
The geometry of the blank surface is measured using on-machine measurement (OMM). The real blank surface is reconstructed using the non-uniform rational basis spline (NURBS) method. The angle-based flattening (ABF) algorithm is used to flatten the reconstructed blank surface. The dense points are extracted from the pattern on the image using the OpenCV library. Then, the dense points are quickly located on the complex surfaces to generate the tool paths.
Findings
By flattening the reconstructed surface and creating the mapping between the contour points and the planar mesh triangular patches, the tool paths can be regenerated to keep the contour of the pattern on the deformed thin-walled surface.
Originality/value
The proposed method can adjust the tool paths according to the deformation of the thin-walled part. The consistency of sculpting patterns is improved.
Details
Keywords
Huirong He, Jida Chen, Shengtao Zhang, Minhui Liao, Lingxing Li, Wei He, Yuanming Chen and Shijin Chen
This paper aims to propose a modified full-additive method (MFAM) to fabricate fine copper lines for high density interconnection (HDI) printed circuit boards (PCBs). In addition…
Abstract
Purpose
This paper aims to propose a modified full-additive method (MFAM) to fabricate fine copper lines for high density interconnection (HDI) printed circuit boards (PCBs). In addition, the surface of the fine copper lines is treated with a brown oxidation process to obtain good adhesion between the copper and the dielectric resin.
Design/methodology/approach
Fine copper lines fabricated by MFAM were observed to evaluate the undercut quality, in comparison to undercut quality of copper lines fabricated by the semi-additive method and the subtractive method. The effect of the thickness of the dry film on the quality of the copper plating was investigated to obtain the regular shape of fine lines. The fine copper lines treated with the brown oxidation process were also examined to generate a coarse surface microstructure to improve the adhesion between the copper and the dielectric resin. The cross section and surface of as-fabricated fine copper lines were characterized using an optical microscope, a scanning electron microscope and an atomic force microscope.
Findings
MFAM has the potential to fabricate high-performance fine copper lines for HDI PCBs. Undercut of as-fabricated fine copper lines could be prevented to meet the design requirement of impedance. In addition, fine copper lines exhibit enough adhesive force to laminate with dielectric resin after the brown oxidation process.
Originality/value
MFAM, with the advantages of high efficiency and being a facile process, is developed to fabricate high-quality fine copper lines for industrial HDI PCB manufacture.
Details
Keywords
Xiaowei Li, Jia Liu, Shengtao Zhang, Wei He, Shijin Chen, Zhidan Li and Jida Chen
– This paper aims to develop an ideal technique for the preparation of print circuit boards (PCBs) with ladder conductive lines on practical industrial process lines.
Abstract
Purpose
This paper aims to develop an ideal technique for the preparation of print circuit boards (PCBs) with ladder conductive lines on practical industrial process lines.
Design/methodology/approach
First, the raw materials of ladder copper-clad laminates were prepared by plating double-sided copper-clad laminates with vertical plating line. Second, etching compensation experiments were designed and conducted to set up the relationships between etching compensation and width of conductive lines on ladder line print circuit boards (LLPCBs). Third, to evaluate the process technique for the preparation of LLPCBs through etching compensation, verification experiments were designed and conducted on a practical industrial process line, and the quality of lines on LLPCBs was observed and evaluated.
Findings
Under the judgment of the quality of conductive lines on LLPCBs as well as the feasibility with a practical industrial process line, the process technique for the preparation of LLPCBs with etching compensation is a simple and reliable method which has the potential to be applied in the industry.
Originality/value
It is the first successful report of a new method that produces LLPCBs with etching compensation and has the potential to be applied in the industry.