Thermal aging effect on the failure loads of adhesively strap joints

2019 ◽  
Vol 53 (26-27) ◽  
pp. 3701-3713 ◽  
Author(s):  
Kadir Turan
Keyword(s):  
Thermal Aging ◽  
Experimental Studies ◽  
Aging Treatment ◽  
Composite Plates ◽  
Aging Effect ◽  
Tensile Tests ◽  
Fibre Reinforcement ◽  
Static Tensile ◽  
Failure Loads ◽  
Reinforcement Angle

In this study, the effects of thermal aging on failure loads in adhesively strap joints were investigated. Thermal aging treatment was applied to the woven glass fibre/epoxy composite plates with eight-layered 0° fibre reinforcement angle, epoxy-based adhesive and to the adhesively strap joints produced with these materials. The strength of the adhesively strap joints of single strap and double strap was determined by static tensile tests. Three conditions were analyzed in the thermal aging process. The first group samples were thermally aged at a temperature of 75, 100 and 150℃ with a constant time of 4 h. The second group samples were thermally aged at a constant temperature of 150℃ for 2, 4, 6 and 8 h and the third group samples were kept at room temperature (not aged). The failure loads of samples which are exposed to thermal aging were compared with the failure loads of the non-aged samples. As a result of experimental studies, it has been determined that the failure loads of thermally aged samples have increased by 27.7% to 133.1%.

scholarly journals Properties of the AZ31 Magnesium Alloy Round Bars Obtained in Different Rolling Processes / Własności Prętów Okrągłych Ze Stopu Magnezu AZ31 Otrzymanych W Różnych Procesach Walcowania

2015 ◽  
Vol 60 (4) ◽  
pp. 3001-3006 ◽  
Author(s):  
A. Stefanik ◽  
P. Szota ◽  
S. Mróz ◽  
T. Bajor ◽  
H. Dyja
Keyword(s):  
Magnesium Alloy ◽  
Rolling Mill ◽  
Energy Demand ◽  
Experimental Studies ◽  
Tensile Tests ◽  
Modern Method ◽  
Extrusion Process ◽  
Mg Alloy ◽  
Static Tensile ◽  
Skew Rolling

Currently magnesium alloy bars are manufactured mainly in the extrusion process. This method has some drawbacks, which include: low process capacity, considerable energy demand, small length of finished products. Therefore it is purposeful to develop efficient methods for manufacturing of Mg alloy products in the form of bars, such methods include groove rolling and three-high skew rolling processes. Modified stretching passes provide change in material plastic flow, which contributes to the occurrence of the better distribution of stress and strain state than in the case of rolling in classical stretching passes. One of the modern method of Mg alloy bars production is rolling in a three-high skew rolling mill, which allows to set in a single pass a larger deformation compared to the rolling in the stretching passes. The paper presents the results of experimental studies of the AZ31 round bars production in the modified stretching passes and in the three-high skew rolling mill. The study of microstructural changes, hardness and the static tensile tests were made for as-cast and ready-rolled bars in both analyzed technologies.

Effect of temperature and geometrical parameters on mechanical properties of pin-loaded fiber metal laminate joints

2017 ◽  
Vol 51 (22) ◽  
pp. 3163-3173 ◽  
Author(s):  
Shiming Zu ◽  
Zhengong Zhou ◽  
Yuan Zhao ◽  
Jipeng Zhang ◽  
Jiazhen Zhang
Keyword(s):  
Mechanical Properties ◽  
Failure Modes ◽  
Tensile Tests ◽  
Effect Of Temperature ◽  
Geometrical Parameters ◽  
Fiber Metal Laminate ◽  
Static Tensile ◽  
Failure Loads ◽  
Fiber Metal ◽  
Loaded Fiber

To investigate the effect of temperature and geometrical parameters on the mechanical properties of pin-loaded fiber metal laminate joints, experiments were performed by means of static tensile tests. The joints of varied width-to-diameter ratios ( W/ D = 2, 3, 4) and edge distance-to-diameter ratios ( E/ D = 1, 2, 3, 4) were experimentally investigated at room temperature. It was found that ultimate failure load increased with the increase of the ratio of W/ D or E/ D. The dominant failure mode was bearing failure. Shear-out and net-tension failures were more easily caused as the pin hole was located closer to the edge of the specimen. Also, to explore the effect of temperature on the bearing responses of fiber metal laminate joints, three typical joint configurations ( W/ D = 4, E/ D = 4; W/ D = 4, E/ D = 1; and W/ D = 2, E/ D = 4) were tested at high temperature, which ranged from 40℃ to 120℃. The test results clearly show that failure loads of joint decrease with the increase of the test temperature. The failure modes of the fiber metal laminate joints were predominantly affected by high test temperatures. The present work provides supporting information for the design of the fiber metal laminate joints.

Calculation And Experimental Substantiation Of Optimal Design Of The Welded Joint Of Plates On Соver Plates

2020 ◽  
pp. 17-24
Keyword(s):  
Welded Joint ◽  
Experimental Studies ◽  
Engineering Calculation ◽  
Tensile Tests ◽  
Physical Nonlinearity ◽  
Steel Plates ◽  
Optimal Parameters ◽  
Actual Problem ◽  
Numerical Research ◽  
Cover Plates

The article is devoted to the actual problem of assigning optimal parameters for connecting steel plates on cover plates with angular welds that are widely used in construction practice. The article presents the results of a comprehensive study of operation of a welded assembly of the plates connection on cover plates. An algorithm is proposed for determining the optimal parameters of a welded joint with fillet welds on the cover plates, which makes it possible to obtain a strength balanced connection. The results of full-scale tensile tests of models were presented. These results confirmed the correctness of the assumed design assumptions, and made it possible to obtain a form of destruction, not characteristic and not described in the normative literature, expressed by cutting the main elements along the length of the overlap in the joint. The possibility of such a form of destruction was confirmed by the results of numerical research in a nonlinear formulation. The optimal parameters of the nodal welded joint determined by engineering calculation are confirmed by experimental studies, as well as by the results of numerical experiments on models of calculation schemes, taking into account the physical nonlinearity of the material operation. The obtained dependence for determining the bearing capacity of the joint by the cut-off mechanism and the expression for limiting the overlap length of the cover plates will make it possible to predict the nature of the fracture and design equally strong joints.

Progressive damage characteristics of screwed single-lap CFRPI-metal joint subjected to tensile loading at RT and 350°C

2021 ◽  
pp. 002199832098559
Author(s):  
Yun-Tao Zhu ◽  
Jun-Jiang Xiong ◽  
Chu-Yang Luo ◽  
Yi-Sen Du
Keyword(s):  
Damage Model ◽  
Tensile Loading ◽  
Tensile Tests ◽  
Displacement Curve ◽  
Progressive Damage ◽  
Damage Characteristics ◽  
Metal Joint ◽  
Static Tensile ◽  
Strength And Stiffness ◽  
Progressive Damage Model

This paper outlines progressive damage characteristics of screwed single-lap CFRPI-metal joints subjected to tensile loading at RT (room temperature) and 350°C. Quasi-static tensile tests were performed on screwed single-lap CCF300/AC721-30CrMnSiA joint at RT and 350°C, and the load versus displacement curve, strength and stiffness of joint were gauged and discussed. With due consideration of thermal-mechanical interaction and complex failure mechanism, a modified progressive damage model (PDM) based on the mixed failure criterion was devised to simulate progressive damage characteristics of screwed single-lap CCF300/AC721-30CrMnSiA joint, and simulations correlate well with experiments. By using the PDM, the effects of geometry dimensions on mechanical characteristics of screwed single-lap CCF300/AC721-30CrMnSiA joint were analyzed and discussed.

scholarly journals The Performance of CR180IF and DP600 Laser Welded Steel Sheets under Different Strain Rates

Materials ◽  
2021 ◽  
Vol 14 (6) ◽  
pp. 1553
Author(s):  
Mária Mihaliková ◽  
Kristína Zgodavová ◽  
Peter Bober ◽  
Anna Špegárová
Keyword(s):  
Sheet Steel ◽  
Testing Machine ◽  
Dynamic Test ◽  
Tensile Tests ◽  
Joint Surface ◽  
Strain Rates ◽  
Interstitial Free ◽  
Welded Steel ◽  
Steel Sheets ◽  
Static Tensile

The presented research background is a car body manufacturer’s request to test the car body’s components welded from dissimilar steel sheets. In view of the vehicle crew’s protection, it is necessary to study the static and dynamic behavior of welded steels. Therefore, the influence of laser welding on the mechanical and dynamical properties, microstructure, microhardness, and welded joint surface roughness of interstitial free CR180IF and dual-phase DP600 steels were investigated. Static tensile tests were carried out by using testing machine Zwick 1387, and dynamic test used rotary hammer machine RSO. Sheet steel was tested at different strain rates ranging from 10−3 to 103 s−1. The laser welds’ microstructure and microhardness were evaluated in the base metal, heat-affected zone, and fusion zone. The comprehensive analysis also included chemical analysis, fracture surface analysis, and roughness measurement. The research results showed that the strain rate had an influence on the mechanical properties of base materials and welded joints. The dynamic loading increases the yield stress more than the ultimate tensile strength for the monitored steels, while the most significant increase was recorded for the welded material.

scholarly journals Investigations on arc brazing for galvanized heavy steel plates in steel and shipbuilding

2021 ◽  
Author(s):  
Philipp Andreazza ◽  
Andreas Gericke ◽  
Knuth-Michael Henkel
Keyword(s):  
Low Cost ◽  
Thin Sheet ◽  
Steel Structures ◽  
Tensile Tests ◽  
Fatigue Tests ◽  
Steel Plates ◽  
Galvanized Steel ◽  
Filler Materials ◽  
Static Tensile ◽  
Brazed Joints

AbstractArc brazing with low-melting copper-based filler materials, which has long been established and standardized in the thin sheet sector, offers numerous advantages in the processing of predominantly electrolytically galvanized steel structures. In steel and shipbuilding, on the other hand, equipment parts made of thick steel sheets are hot-dip galvanized at low cost and with good corrosion-inhibiting properties. Quality welding of such constructions is not possible without special precautions such as removing the zinc layer and subsequent recoating. With regard to greater plate thicknesses, arc brazing was analyzed in these investigations as an alternative joining method with regard to its suitability for practical use. Within the scope of the investigations, CuSi3Mn, CuMn12Ni2, and four different aluminum bronzes were examined on different sheet surface conditions with regard to the geometrical and production parameters. This was carried out by build-up and connection brazing, executed as butt and cross joints. Quasi-static tensile tests and fatigue tests were used to assess the strength behavior. In addition, metallographic analyses are carried out as well as hardness tests. The suitability for multi-layer brazing and the tendency to distortion were also investigated, as well as the behavior of arc brazed joints under corrosive conditions.

scholarly journals Experimental and Numerical Buckling Analyses of Laminated Composite Plates under Temperature Effects

2010 ◽  
Vol 19 (4) ◽  
pp. 096369351001900 ◽  
Author(s):  
Emin Ergun
Keyword(s):  
Composite Plate ◽  
Numerical Solutions ◽  
Laminated Composite ◽  
Composite Plates ◽  
Buckling Load ◽  
Fibre Reinforcement ◽  
Stacking Sequence ◽  
Laminated Composite Plates ◽  
Different Temperatures ◽  
Good Agreement

The aim of this study is to investigate, experimentally and numerically, the change of critical buckling load in composite plates with different ply numbers, orientation angles, stacking sequences and boundary conditions as a function of temperature. Buckling specimens have been removed from the composite plate with glass-fibre reinforcement at [0°]i and [45°]i (i= number of ply). First, the mechanical properties of the composite material were determined at different temperatures, and after that, buckling experiments were done for those temperatures. Then, numerical solutions were obtained by modelling the specimens used in the experiment in the Ansys10 finite elements package software. The experimental and numerical results are in very good agreement with each other. It was found that the values of the buckling load at [0°] on the composite plates are higher than those of other angles. Besides, symmetrical and anti-symmetrical conditions were examined to see the effect of the stacking sequence on buckling and only numerical solutions were obtained. It is seen that the buckling load reaches the highest value when it is symmetrical in the cross-ply stacking sequence and it is anti-symmetrical in the angle-ply stacking sequence.

scholarly journals Thermal aging characterization of composite plates and honeycomb sandwiches by electromechanical measurement

2017 ◽  
Vol 142 (6) ◽  
pp. 3691-3702 ◽  
Author(s):  
Elhadji Barra Ndiaye ◽  
Hugues Duflo ◽  
Pierre Maréchal ◽  
Pascal Pareige
Keyword(s):  
Thermal Aging ◽  
Composite Plates

Comparative study of thermoplastic liner materials with regard to mechanical and permeation barrier properties before and after cyclic thermal aging

2021 ◽  
Vol 63 (4) ◽  
pp. 311-316
Author(s):  
Simon Backens ◽  
Jan Siering ◽  
Stefan Schmidt ◽  
Nikolai Glück ◽  
Wilko Flügge
Keyword(s):  
Thermal Aging ◽  
Barrier Properties ◽  
Tensile Tests ◽  
Polyamide 6 ◽  
Pressure Vessels ◽  
Cross Linking ◽  
Polyamide 12 ◽  
Type Iv ◽  
Before And After ◽  
Permeation Properties

Abstract Lightweight pressure vessels of type IV for hydrogen storage consist of a thermoplastic inner liner, commonly from polyethylene or polyamide. The liner is the permeation barrier against the compressed gas and must prevent the formation of cracks, also after temperature changes, for example after refueling processes. In the present work high-density polyethylene, cross-linked polyethylene, polyamide 6 and polyamide 12 were characterized by tensile tests, single notch impact tests and permeations measurements before and after a cyclic thermal aging process. The aging only lead to slight changes of mechanical properties due to post-crystallization, but to a significant decrease of permeation properties. This decrease was contributed to weakened, amorphous regions where chain splitting occurred. Considerable differences in properties resulted from different peroxide cross-linking times of polyethylene at the same temperature. A longer holding time at 200 °C led to an improvement in impact strength by a factor of more than three. However, the permeation properties decreased by about 50 %, indicating that peroxide cross-linking in the melt inhibited the formation of crystalline regions.

Sign in / Sign up

Export Citation Format

Share Document