scholarly journals Effect of In-Situ Synthesized Boride Phases on the Impact Behavior of Iron-Based Composites Reinforced by B4C Particles

Metals ◽  
2020 ◽  
Vol 10 (5) ◽  
pp. 554
Author(s):  
Fehmi Nair ◽  
Mustafa Hamamcı
Keyword(s):  
Contact Forces ◽  
Impact Behavior ◽  
Iron Matrix ◽  
Impact Tests ◽  
B4c Particles ◽  
Iron Based ◽  
In Situ Reactions ◽  
Boride Phases ◽  
The Impact

The objective of this study is to investigate the impact behavior of iron-based composites reinforced with boron carbide (B4C) particles and in-situ synthesized iron borides (Fe2B/FeB). The composite specimens (Fe/B4C) were fabricated by hot-pressing under a pressure of 250 MPa at 500 °C, and sintered at a temperature of 1000 °C. The effects of the reinforcement ratio on the formation of in-situ borides and impact behavior were investigated by means of different volume fractions of B4C inside the iron matrix: 0% (un-reinforced), 5%, 10%, 20%, and 30%. Drop-weight impact tests were performed by an instrumented Charpy impactor on reinforced and un-reinforced test specimens. The results of the impact tests were supported with microstructural and fractographical analysis. As a result of in-situ reactions between the Fe matrix and B4C particles, Fe2B phases were formed in the iron matrix. The iron borides, formed in the iron matrix during sintering, heavily affected the hardness and the morphology of the fractured surface. Due to the high amount of B4C (over 10%), porosity played a major role in decreasing the contact forces and fracture energy. The results showed that the in-situ synthesized iron boride phases affect the impact properties of the Fe/B4C composites.

Impact Strength of High Density Solid-State Microcellular Polycarbonate Foams

2000 ◽  
Vol 123 (2) ◽  
pp. 229-233 ◽  
Author(s):  
Chris Barlow ◽  
Vipin Kumar ◽  
Brian Flinn ◽  
Rajendra K. Bordia ◽  
John Weller
Keyword(s):  
Solid State ◽  
Impact Strength ◽  
Cell Size ◽  
High Density ◽  
Gas Content ◽  
Impact Behavior ◽  
Strong Function ◽  
Impact Tests ◽  
Izod Impact ◽  
The Impact

The effect of density (relative densities 0.33 to 0.90) on the impact behavior of microcellular polycarbonate (PC) was investigated. Cell size and foaming gas content were also considered. Flexed-beam Izod impact tests were conducted and the impact strength of these foams appears to be a strong function of both density and cell size. The impact strength was observed to improve over the unprocessed polycarbonate’s impact strength for foams with relative densities of 60 percent and above. In terms of cell size, the impact strength increased with increasing cell size at a given density.

Effect of superelastic shape memory alloy wires on the impact behavior of carbon fiber reinforced in situ polymerized poly(butylene terephthalate) composites

2011 ◽  
Vol 65 (5) ◽  
pp. 863-865 ◽  
Author(s):  
J. Aurrekoetxea ◽  
J. Zurbitu ◽  
I. Ortiz de Mendibil ◽  
A. Agirregomezkorta ◽  
M. Sánchez-Soto ◽  
...  
Keyword(s):  
Carbon Fiber ◽  
Shape Memory Alloy ◽  
Shape Memory ◽  
Impact Behavior ◽  
Fiber Reinforced ◽  
Butylene Terephthalate ◽  
Carbon Fiber Reinforced ◽  
The Impact

EFFECT OF HEAT TREATMENT ON (Cr, Fe)7C3/γ-Fe COATINGS IN SITU SYNTHESIZED BY VACUUM ELECTRON BEAM IRRADIATION

2017 ◽  
Vol 24 (Supp02) ◽  
pp. 1850028
Author(s):  
BINFENG LU ◽  
YUNXIA CHEN ◽  
MENGJIA XU
Keyword(s):  
Heat Treatment ◽  
Wear Resistance ◽  
Electron Beam ◽  
Impact Toughness ◽  
Composite Layer ◽  
Test Machine ◽  
Iron Matrix ◽  
Heat Treated ◽  
The Impact

(Cr, Fe)7C3/[Formula: see text]-Fe composite layer has been in situ synthesized on a low carbon steel surface by vacuum electron beam VEB irradiation. The synthesized samples were then subdued to different heat treatments to improve their impaired impact toughness. The microstructure, impact toughness and wear resistance of the heat-treated samples were studied by means of optical microscope (OM), X-ray diffraction (XRD), scanning electron microscope (SEM), microhardness tester, impact test machine and tribological tester. After heat treatment, the primary and eutectic carbides remained in their original shape and size, and a large number of secondary carbides precipitated in the iron matrix. Since the Widmanstatten ferrite in the heat affected zone (HAZ) transformed to fine ferrite completely, the impact toughness of the heat-treated samples increased significantly. The microhardness of the heat-treated samples decreased slightly due to the decreased chromium content in the iron matrix. The wear resistance of 1000[Formula: see text]C and 900[Formula: see text]C heat-treated samples was almost same with the as-synthesized sample. While the wear resistance of the 800[Formula: see text]C heat-treated one decreased slightly because part of the austenite matrix had transformed to ferrite matrix, which reduced the bonding of carbides particulates.

Spark Plasma Sintering of Silicon Nitride-Boron Carbide Composites

2008 ◽  
Vol 403 ◽  
pp. 225-226
Author(s):  
E. Ayas ◽  
A. Kalemtas ◽  
Gürsoy Arslan ◽  
Alpagut Kara ◽  
Ferhat Kara
Keyword(s):  
Electrical Resistivity ◽  
Spark Plasma Sintering ◽  
Xrd Analysis ◽  
Sintering Process ◽  
Electrically Conductive ◽  
Plasma Sintering ◽  
B4c Particles ◽  
Spark Plasma ◽  
In Situ Reactions

Si3N4-B4C composites containing fine and coarse B4C particles were produced using Al2O3 and Y2O3 as sintering additives via spark plasma sintering (SPS) technique. Phase assemblages of the produced composites were determined by XRD analysis. Si3N4, B4C and in situ formed SiC, h-BN and Si phases were observed. Even when incorporated in significant amounts, B4C was consumed readily in the Si3N4 based system. Consequently, full densification of these composites was found to be a very difficult task due to the simultaneous in-situ reactions, even in fast sintering process. Electrical resistivity measurements carried out at room temperature indicated that addition of both fine and coarse B4C particles decreased the electrical resistivity by several orders of magnitude due to the formation of electrically conductive in-situ phases, mainly SiC and metallic Si.

Computer Simulation of a Transportation Package Impacting Concrete and Soil Targets

2004 ◽  
Author(s):  
S. N. Huang ◽  
S. S. Shiraga ◽  
L. M. Hay
Keyword(s):  
Numerical Simulation ◽  
Computer Simulation ◽  
Impact Test ◽  
Impact Behavior ◽  
Test Results ◽  
Hypothetical Accident ◽  
Simulation Results ◽  
Accident Conditions ◽  
The Impact

This paper compares transportation mockup cask impact test results onto real surfaces with FEA numerical simulation results. The impact test results are from a series of cask impact tests that were conducted by Sandia National Laboratories (Gonzales 1987). The Sandia tests were conducted with a half-scale instrumented cask mockup impacting an essentially unyielding surface, in-situ soil, concrete runways, and concrete highways. The cask numerical simulations with these same surfaces are conducted with ABAQUS/Explicit, Version 5.8, The results are then compared and evaluated to access the viability of using numerical simulation to predict the impact behavior of transportation casks under hypothetical accident conditions.

Influence of Internal Pressure on the Impact Behavior of Steel Pipelines

1996 ◽  
Vol 118 (4) ◽  
pp. 464-471 ◽  
Author(s):  
N. Jones ◽  
R. S. Birch
Keyword(s):  
Experimental Data ◽  
Mild Steel ◽  
Internal Pressure ◽  
Wall Thickness ◽  
Critical Values ◽  
Impact Behavior ◽  
Steel Pipes ◽  
Impact Tests ◽  
The Impact ◽  
Gas Pressures

This article presents some experimental data recorded from 54 impact tests on pressurized mild steel pipes. The pipes were fully clamped across a span which was ten times the outside pipe diameter of 60 mm. The pipes had a wall thickness of 1.70 mm and were impacted laterally by a rigid wedge indenter at the mid-span and one-quarter-span positions. The impact velocities ranged up to 13.6 m/s and caused large inelastic indentations for the lower values and at higher values a loss of integrity which could occur underneath the indenter and/or at an end support. The critical values for the two failure energies were obtained for a range of internal gas pressures.

Vibrations due to Impact in a Non Ideal Mechanical System With a Non-Linear Hertzian Contact Model

2014 ◽  
Author(s):  
Helio A. Navarro ◽  
Jose M. Balthazar ◽  
Reyolando M. L. R. F. Brasil
Keyword(s):  
Mechanical System ◽  
Rigid Wall ◽  
Contact Forces ◽  
Hertzian Contact ◽  
Impact Behavior ◽  
Steady State Responses ◽  
Post Impact ◽  
The Impact ◽  
The Mathematical Model ◽  
State Responses

This work analyses the post impact behavior of a mechanical system consisting of an oscillator and an unbalanced non–ideal electrical motor. The impact between the mechanical system and a rigid wall is based on the assumption that the impacting bodies undergo local deformations. The method used in the present work is similar to the Discrete Element Method for particle systems modeled with a “soft–sphere” mechanism. The contact forces are modeled using a nonlinear damped Hertzian Spring-Dashpot system. The mathematical model of the mechanical system is represented by a set of nonlinear ordinary differential equations. The transient and steady-state responses are discussed. As the motor is considered a non ideal energy source, the Sommerfeld effect is also analyzed. The impact model is first applied for a single freely falling particle and then in the proposed mechanical system. Non-dimensional expressions for the contact force and numerical simulations of the mechanical system behavior are also presented.

scholarly journals Impact Behavior of a Rotating Rigid Body with Impact and Viscous Friction

2020 ◽  
Vol 2020 ◽  
pp. 1-11 ◽  
Author(s):  
Dorian Cojocaru ◽  
Dan B. Marghitu
Keyword(s):  
Viscous Friction ◽  
Friction Model ◽  
Contact Forces ◽  
Hertzian Contact ◽  
Impact Behavior ◽  
Element Analysis ◽  
Friction Parameters ◽  
Friction Function ◽  
Coulomb Dry Friction ◽  
The Impact

The impact between a rotating link and a solid flat surface is considered. For the impact, we consider three distinct periods: elastic period, elastoplastic period, and restitution period. A Hertzian contact force is considered for the elastic period. Nonlinear contact forces developed from finite element analysis are used for the remaining two phases. The tangential effect is taken into account considering a friction force that combines the Coulomb dry friction model and a viscous friction function of velocity. Simulations results are obtained for different friction parameters. An experimental setup was designed to measure the contact time during impact. The experimental and simulation results are compared for different lengths of the link.

Tailoring the impact behavior of polyamide 6 ternary blends via a hierarchical core–shell structure in situ formed in melt mixing

RSC Advances ◽  
2015 ◽  
Vol 5 (19) ◽  
pp. 14592-14602 ◽  
Author(s):  
Rui Dou ◽  
Chao Shen ◽  
Bo Yin ◽  
Ming-bo Yang ◽  
Bang-hu Xie
Keyword(s):  
Shell Structure ◽  
Polyamide 6 ◽  
Impact Behavior ◽  
Ternary Blend ◽  
Core Shell ◽  
Ternary Blends ◽  
Melt Mixing ◽  
Core Shell Structure ◽  
The Impact

The hierarchical core–shell structure in PA6/HDPE-g-MA/EPDM ternary blend was firstly formed using simple melt mixing. A super toughness PA6 ternary blends with HDPE-g-MA multi-core structure was obtained.

Sign in / Sign up

Export Citation Format

Share Document