scholarly journals Stiffness Calculation Method and Stiffness Characteristic Analysis of Bolted Connectors

2019 ◽  
Vol 2019 ◽  
pp. 1-11 ◽  
Author(s):  
Shi-kun Lu ◽  
Deng-xin Hua ◽  
Yan Li ◽  
Fang-yuan Cui ◽  
Peng-yang Li
Keyword(s):  
Surface Roughness ◽  
Bolted Joints ◽  
Joint Surface ◽  
Characteristic Analysis ◽  
Surface Stiffness ◽  
Stiffness Characteristic ◽  
Calculation Results ◽  
Bolt Connection ◽  
The Relationship ◽  
Effect Of Surface

At present, few scholars have studied the effect of surface roughness on assembly stiffness. The influence of the joint surface stiffness on the overall stiffness is neglected. In this paper, a new method for calculating the stiffness of bolted joints is presented. The effect of joint surface stiffness on the overall stiffness is considered. Firstly, the relationship between load and displacement between cylinder and cylinder (including the joint surface with certain roughness) is studied, and the stiffness characteristic expression of the joint surface is obtained; the results are compared with the traditional stiffness calculation theory, and then, the influence of bolt connection surface on bolt connection is studied and compared with the stiffness calculation results of traditional bolt connection. The results show that the theoretical model presented in this paper is more practical.

Effect of Surface Roughness and Joint Material on Torque-Tension Relationship in Threaded Fasteners

2005 ◽  
Author(s):  
S. A. Nassar ◽  
T. S. Sun
Keyword(s):  
Surface Roughness ◽  
Load Level ◽  
Friction Torque ◽  
Joint Surface ◽  
Specific Level ◽  
Tightening Torque ◽  
Safety And Reliability ◽  
The Stability ◽  
Engineering Practices ◽  
Effect Of Surface

An experimental study is presented in order to investigate the effect of surface roughness on the torque-tension relationship in bolted assemblies. Three levels of surface roughness are considered for the fastener underhead and the joint surface; namely, low, medium, and high levels of surface roughness. The study is conducted for two joint materials, two fastener classes, and for coarse and fine threads. In this study, the torque-tension data is expressed in terms of the value of the nut factor as well as its scatter. The effect of the number of tightenings on surface roughness and on the torque-tension relationship is investigated as well. The surface roughness is measured before tightening, and after each loosening using a WYKO optical profiling system. An M12 fastener is used in this study. Both fine and coarse threads and fastener material Classes 8.8 and 10.9 for M12 fasteners are used in this study. The torque-tension data is analyzed for both steel and aluminum joints. The safety and reliability of bolted assemblies are mainly determined by the level and the stability of the clamp load provided by the initial tightening of the threaded fastener. The value of initial clamp load, which is achieved by a specific level of tightening torque, is highly sensitive to the friction torque components. This study provides an insight into the reliability of the existing engineering practices for estimating the clamp load level from the tightening torque. Hence, the findings of the study would help enhance the reliability and the safety of bolted assemblies, especially in critical applications.

Influence of paper properties on adhesive strength of starch gluing

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Claudia Anna Dohr ◽  
Ulrich Hirn
Keyword(s):  
Surface Roughness ◽  
Contact Angle ◽  
Main Parameter ◽  
External Pressure ◽  
Liquid Penetration ◽  
Surface Wetting ◽  
Paper Properties ◽  
Substantial Correlation ◽  
The Relationship ◽  
Effect Of Surface

Abstract The effect of paper properties on the strength of starch gluing for Kraft sack papers has been investigated. We analyzed the effect of surface roughness, wettability and glue penetration. Surface roughness was found not to be related to gluing strength, also surface wetting measured by contact angle showed only a weak relation. Liquid penetration measured by ultrasound (ULP) was found to have a substantial correlation to gluing strength. Comparing ULP liquid penetration speed with actual glue uptake during the gluing process we found that they are only moderately connected. We are attributing this to the fact that the penetration and spreading of the glue on the paper is driven by applying an external pressure during the gluing process, which is not the case for the liquid penetration measurement. Investigating how asymmetrical glue penetration affects gluing strength we found that the relationship was low. The best indication for gluing strength turned out to be the surface wetting/substrate swelling parameter from the ultrasonic liquid penetration measurement. We conclude that the main parameter capturing gluing strength combines the influence of fiber wetting and penetration of the glue into the fibers.

Effect of surface roughness and hardness of leadframe on the bondability of gold wedge bonds

2019 ◽  
Vol 36 (2) ◽  
pp. 62-67
Author(s):  
Muhammad Nubli Zulkifli ◽  
Fuaida Harun ◽  
Azman Jalar
Keyword(s):  
Surface Roughness ◽  
Ultrasonic Vibration ◽  
Design Methodology ◽  
Laser Interferometer ◽  
Vertical Axis ◽  
Content Type ◽  
Pull Strength ◽  
The Relationship ◽  
Effect Of Surface

Purpose This paper aims to analyze the effect of surface roughness and hardness of leadframe on the bondability of gold (Au) wedge bond using in situ inspection of laser interferometer and its relationship with the deformation and wire pull strength. Design/methodology/approach The in situ inspection of ultrasonic vibration waveform through the changes of vertical axis (y-axis) amplitude of wire bonder capillary was carried out using laser interferometer to analyze the formation of Au wedge bond. The relationship between the changes of ultrasonic waveform of capillary with the deformation and the pull strength was analyzed to evaluate the bondability of Au wedge bonds. Findings It was observed that the changes in vertical axis amplitude of ultrasonic vibration waveform of wire bonder capillary can be used to describe the process of bonding formation. The loss of ultrasonic energy was exhibited in ultrasonic vibration waveform of wire bonding on leadframe that has higher value of roughness (leadframe A) as compared to that of leadframe that has lower value of roughness (leadframe B). The lower pull strength obtained by Au wedge bond further confirms the reduction of bond formation because of the higher deformation on leadframe A as compared to that of leadframe B. Originality/value The relationship between in situ measurement using laser interferometer with the bondability or deformation and wire pull strength of Au wedge bonds on different surface roughness and hardness of leadframes is still lacking. These findings provide a valuable data in analyzing the bonding mechanisms that can be identified based on the in situ measurement of ultrasonic vibration and the bondability of Au wedge bonds.

Strength of Ductile Adhesive Butt Joint Bonded with Dissimilar Adherents: Effect of Surface Roughness

2014 ◽  
Vol 554 ◽  
pp. 366-370 ◽  
Author(s):  
Nurul Atikah ◽  
Mohd Afendi ◽  
Siti Hirmaliza ◽  
Mohd Shukry Abdul Majid ◽  
Nurul Amira ◽  
...  
Keyword(s):  
Surface Roughness ◽  
Static Loading ◽  
Testing Machine ◽  
Butt Joint ◽  
Butt Joints ◽  
Universal Testing ◽  
Different Types ◽  
Relationship Of ◽  
The Relationship ◽  
Effect Of Surface

The purpose of this project is to study the influence of the macroscopic state of surface roughness of the dissimilar adherent on the strength of adhesive joint. In this project, several types of sandpaper were used to produce different surface roughness of stainless steel and aluminium alloy adherents. All bonding surfaces were polished with different types of sandpaper. Butt joints of dissimilar adherent specimen were produced using a ductile adhesive (i.e. Araldite®Standard) with same bond thickness. The specimens were tested under static loading condition using universal testing machine (UTM) to investigate the relationship of the surface roughness and bond strength.

scholarly journals Polishing Characteristics and Mechanism of Polishing Glass Substrate Using Suede Pad with Fine Micrometer-Sized Pores

2022 ◽  
Vol 16 (1) ◽  
pp. 52-59
Author(s):  
Michio Uneda ◽  
Nodoka Yamada ◽  
Yoshihiro Tawara ◽  
◽  
Keyword(s):  
Surface Roughness ◽  
Friction Coefficient ◽  
Chemical Mechanical Polishing ◽  
Glass Substrate ◽  
Removal Rate ◽  
Thickness Direction ◽  
Glass Substrates ◽  
Pad Conditioning ◽  
The Relationship ◽  
Effect Of Surface

Chemical mechanical polishing (CMP) using a suede polishing pad is an essential fabrication process for glass substrates that require ultra-high planarization. However, the effect of surface asperities of the suede pad on its polishing characteristics is not completely understood because the structure of the suede pad in the thickness direction is not constant, and its surface asperities can easily change during the pad conditioning or marathon polishing processes. In addition, many previous studies have discussed the polishing mechanism using a suede pad; however, these studies used suede pads with a pore size of approximately 100 μm. This paper discusses the polishing characteristics of a suede pad with fine micrometer-sized pores by clarifying the relationships between the removal rate, friction coefficient, pore parameters, and roughness as the pad surface asperities. In this study, a series of marathon polishing tests were performed with and without conditioning. It was discovered that the removal rate was affected not only by the pore parameters but also by the surface roughness of the suede pad with fine pores. The relationship between the removal rate and the friction coefficient changed owing to the influence of pad conditioning, and this change is significant when the break-in conditioning time is short.

Possible examinations of stone machining focused on the relationship between technological parameters and surface quality

2013 ◽  
Vol 4 (1) ◽  
pp. 63-68 ◽  
Author(s):  
Zs. Kun ◽  
I. G. Gyurika
Keyword(s):  
Surface Roughness ◽  
Metal Cutting ◽  
Cutting Speed ◽  
Theoretical Background ◽  
Motion Path ◽  
Depth Of Cut ◽  
Manufacturing Cost ◽  
Technological Parameters ◽  
The Relationship ◽  
Manufacturing Time

Abstract The stone products with different sizes, geometries and materials — like machine tool's bench, measuring machine's board or sculptures, floor tiles — can be produced automatically while the manufacturing engineer uses objective function similar to metal cutting. This function can minimise the manufacturing time or the manufacturing cost, in other cases it can maximise of the tool's life. To use several functions, manufacturing engineers need an overall theoretical background knowledge, which can give useful information about the choosing of technological parameters (e.g. feed rate, depth of cut, or cutting speed), the choosing of applicable tools or especially the choosing of the optimum motion path. A similarly important customer's requirement is the appropriate surface roughness of the machined (cut, sawn or milled) stone product. This paper's first part is about a five-month-long literature review, which summarizes in short the studies (researches and results) considered the most important by the authors. These works are about the investigation of the surface roughness of stone products in stone machining. In the second part of this paper the authors try to determine research possibilities and trends, which can help to specify the relation between the surface roughness and technological parameters. Most of the suggestions of this paper are about stone milling, which is the least investigated machining method in the world.

The effect of surface roughness on AES depth profile.

Shinku ◽  
1987 ◽  
Vol 30 (10) ◽  
pp. 793-798 ◽  
Author(s):  
Masao HIRASAKA ◽  
Masao HASHIBA ◽  
Toshiroh YAMASHINA
Keyword(s):  
Surface Roughness ◽  
Depth Profile ◽  
Effect Of Surface
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