The Study of High Speed Micro-Drilling Performance and Machining Quality of Coated Micro-Drills with Zr-C:H Coatings

2012 ◽  
Vol 591-593 ◽  
pp. 342-346 ◽  
Author(s):  
Wen Hsien Kao ◽  
Yan Liang Su ◽  
Sun Hui Yao ◽  
H.C. Huang ◽  
M.S. Chen
Keyword(s):  
High Speed ◽  
Printed Circuit Board ◽  
Circuit Board ◽  
Hole Drilling ◽  
Closed Field ◽  
Machining Performance ◽  
Machining Quality ◽  
Drilling Performance ◽  
Micro Drilling ◽  
Micro Drill

The Zr-C:H coatings with various C2H2 flow rate were deposited on micro-drills (a diameter of 0.2 mm) used a closed field unbalanced magnetron sputtering system. The ultrahigh speed (drilling speed of 160000 rpm) through-hole drilling printed circuit board tests used to evaluate the drilling performance of the coated micro-drills. The rejection criteria of service lives of the coated micro-drills were evaluated using two different criteria: (1) a nail head ratio greater than 1.5; (2) a drilled hole surface roughness greater than 25.4 μm. Adopting a service life criterion of a nail head ratio of 1.5, the Zr-C:H-5 coating possesses the optimal high-speed machining performance, which yields a micro-drill lifetime of above 6000 drilled holes. It represents a three-fold improvement on that of an uncoated micro-drill and it also improves machining quality.

Influence of Pulsed-DC Power Frequency on Mechanical Properties and High Speed Drilling Application of a-C:H:Zr-x Coatings

2011 ◽  
Vol 328-330 ◽  
pp. 861-867
Author(s):  
Wen Hsien Kao ◽  
Yan Liang Su ◽  
Sun Hui Yao ◽  
S.H. Liu
Keyword(s):  
High Speed ◽  
Printed Circuit Board ◽  
Deposition Process ◽  
Circuit Board ◽  
Hole Drilling ◽  
Closed Field ◽  
Machining Performance ◽  
Dc Power ◽  
Pulsed Dc ◽  
Micro Drill

The a-C:H:Zr-x coatings are deposited on micro-drills using a closed field unbalanced magnetron (CFUBM) sputtering system with pulsed-DC power frequencies in the range 30 kHz to 110 kHz (the x in the term a-C:H:Zr-x is the frequency varied in the deposition process). The hardness of the various coatings is systematically explored. Additionally, the machining performance of the coated micro-drills is investigated by conducting high-speed through-hole drilling tests utilizing Printed Circuit Board (PCB) specimens. The experimental results reveal that the a-C:H:Zr-70 coating has the highest hardness (42 GPa), while the a-C:H:Zr-110 coating has the lowest hardness (26 GPa). In addition, it is shown that the a-C:H:Zr-70 coating increases the life of the micro-drill by a factor of three compared to that of an uncoated micro-drill.

Characterization of drill bit breakage in PCB drilling process based on high-speed video analysis

Circuit World ◽  
2017 ◽  
Vol 43 (3) ◽  
pp. 89-96 ◽  
Author(s):  
Hongyan Shi ◽  
Xiaoke Lin ◽  
Yun Wang
Keyword(s):  
Video Analysis ◽  
High Speed ◽  
Printed Circuit Board ◽  
Circuit Board ◽  
Drilling Process ◽  
Drill Bit ◽  
Content Type ◽  
High Speed Video ◽  
Micro Drill

Purpose The purposes of this paper are to study the characterization of drill bit breakage in printed circuit board (PCB) drilling process based on high-speed video analysis and to provide an important reference for micro drill bit breakage prediction. Design/methodology/approach Based on PCB drilling experiment, the high-speed camera was used to observe the micro drill breakage process and the chip removal process. The variation of chip in the drilling process was studied and one of the key reasons for the drill bit breakage was analysed. Finally, the swing angles’ feature during the breakage process of the micro drill was analysed and researched with the image processing tools of MATLAB. Findings The micro drill was prone to breakage mainly because of the blocked chips. The breakage process of the micro drill can be divided into the stage of stable chips evacuation, the stage of blocked chips and the stage of drill bit breakage. The radians of swing angles were basically in the range of ±0.01 when the drilling possess is normal. But when the radians of swing angles considerably exceeded the range of ±0.01, the micro drill bit may be fractured. Originality/value This paper presented the method to study the characterization of drill bit breakage in the PCB drilling process by using high-speed video analysis technology. Meanwhile, an effective suggestion about monitoring the radians of swing angles to predict the breakage of micro drill bit was also provided.

Measurement of Micro-Drill Breakage during PCB Drilling

2016 ◽  
Vol 836-837 ◽  
pp. 592-599 ◽  
Author(s):  
Xin Huang ◽  
Zhi Shun Chen ◽  
Cheng Yong Wang ◽  
Li Juan Zheng ◽  
Yue Xian Song
Keyword(s):  
Printed Circuit Board ◽  
Circuit Board ◽  
Detection Methods ◽  
Contact Detection ◽  
Contact Type ◽  
Effective Contact ◽  
Detection Circuit ◽  
Micro Drilling ◽  
Pulse Type ◽  
Micro Drill

Due to the weak rigidity of micro-drills and impulse effects, the micro-drill breakage is a common problem in printed circuit board micro-drilling. Traditional micro-drill breakage detection methods and principles, including vacuum-type, laser-type, and contact-type detection, were reviewed in this paper. The comparison of three detection methods showed that the contact-type detection can more satisfy the performance of CNC drilling machine. Three effective contact-detection circuits, including no transformer and rectifier circuit pulse-type, active-type, and trigger-type detection circuit, were introduced. And as a conclusion, differences of these detection methods were compared. Based on the characteristic of three effective micro-drill breakage contact detection circuits, the development trends and designs of innovative detection circuit were proposed to meet the challenges in micro-drill breakage measurement during PCB drilling.

Experimental Study on Cutting Force of High-Speed Micro-Drilling Flexible Printed Circuit Board

2012 ◽  
Vol 723 ◽  
pp. 401-406 ◽  
Author(s):  
Xin Zhang ◽  
Cheng Yong Wang ◽  
Li Juan Zheng ◽  
Lin Fang Wang ◽  
Yue Xian Song
Keyword(s):  
Cutting Force ◽  
High Speed ◽  
Printed Circuit Board ◽  
Thrust Force ◽  
Circuit Board ◽  
Feed Speed ◽  
Printed Circuit ◽  
Flexible Printed Circuit ◽  
Micro Drilling ◽  
Exit Burr

Cutting force is one of the most important parameters in the drilling process of FPC (Flexible printed circuit board). It has a directly affect on the micro-drills’ life and the micro-holes quality. It causes the FPC delamination, pulling of the plastic, the burr of exit hole and other processing defects. In this paper, some experimental investigations of cutting force of high speed micro-drilling are carried out to improve the drilling quality of FPC. The results indicate that the drilling parameters(spindle speed, feed speed and drill-bit diameter) have significant influence on micro-drilling thrust force. The thrust force of drill copper foil is larger than the thrust force of drill adhesiver layer and the thrust force of drill PI layer is the smallest. The larger the thrust force is, the bigger the exit burr is.

The influence of properties of printed circuit board resin and filler on drilling force

Circuit World ◽  
2018 ◽  
Vol 44 (4) ◽  
pp. 165-170
Author(s):  
Hongyan Shi ◽  
Xiaoke Lin ◽  
Qiuxin Yan ◽  
JiaNan Zhang
Keyword(s):  
Measurement System ◽  
Printed Circuit Board ◽  
Force Measurement ◽  
Circuit Board ◽  
Hole Drilling ◽  
Drilling Force ◽  
Content Type ◽  
Printed Circuit ◽  
Micro Drilling ◽  
Force Measurement System

Purpose The purpose of this paper is to study and obtain the influence of resin and filler properties of printed circuit board (PCB) on the drilling force during micro drilling. Design/methodology/approach Experiments were carried out to study the influence of PCB on micro-hole drilling force under high spindle speed. A drilling force measurement system was applied, and then, the influence of resin and filler properties of PCBs on the force was analyzed. The proportion of resin and filler in the PCB was defined as four levels, and the influence of PCBs based on the drilling force measurement was summarized. Findings The drilling force decreased with the decrease in the feed rate, and lower filler (16-30 per cent) and average resin (31-50 per cent) would have a positive impact on the drilling force. At the same time, the size of uniform and fine fillers would help to reduce the drilling force. Originality/value The drilling force measurement system was applied, and the influence of PCBs on force was analyzed, which could provide a reference value on the optimization of the drilling force during micro drilling.

Sign in / Sign up

Export Citation Format

Share Document