Correlation of wear and work in dual pivoted jaw crusher tests

2018 ◽  
Vol 234 (3) ◽  
pp. 334-349
Author(s):  
Juuso Terva ◽  
Kati Valtonen ◽  
Pekka Siitonen ◽  
Veli-Tapani Kuokkala
Keyword(s):  
Flow Stress ◽  
Strain Rate ◽  
Mass Loss ◽  
Lower Amount ◽  
Jaw Crusher ◽  
Rate Dependent ◽  
Sliding Motion ◽  
The Relationship

A laboratory sized jaw crusher with uniform movement of the jaws, the dual pivoted jaw crusher, was used to determine the relationship between wear and work. Wear was concentrated on the jaw plates opposing each other and was measured as mass loss of the specimens. Work was measured directly from the force and displacement of the instrumented jaw, which allowed work to accumulate only from the actual crushing events. The tests were conducted with several jaw geometries and with two motional settings, where the relation of compressive and sliding motion between the jaws was varied. The tests showed that the relation between wear and work was constant in many of the tested cases. In certain tests with larger lateral and faster contact speed, wear occurred at relatively lower amounts of work. This behavior was more definite when the relation of wear and work was investigated using modified Archards wear equation. The results indicate that the lower amount of needed work could stem from the material reaching a dynamic situation, where the flow stress becomes increasingly strain-rate dependent.

A Modified Peric Model for Al-Mg Alloy Sheet with Rate-Independent Initial Yield Stress at Warm Temperatures

2019 ◽  
Vol 287 ◽  
pp. 3-7
Author(s):  
Yong Zhang ◽  
Qing Zhang ◽  
Yuan Tao Sun ◽  
Xian Rong Qin
Keyword(s):  
Flow Stress ◽  
Plastic Strain ◽  
Strain Rate ◽  
Yield Stress ◽  
Constitutive Models ◽  
Mg Alloy ◽  
Initial Yield Stress ◽  
Initial Yield ◽  
Rate Dependent ◽  
Dependent Flow

The constitutive modeling of aluminum alloy under warm forming conditions generally considers the influence of temperature and strain rate. It has been shown by published flow stress curves of Al-Mg alloy that there is nearly no effect of strain rate on initial yield stress at various temperatures. However, most constitutive models ignored this phenomenon and may lead to inaccurate description. In order to capture the rate-independent initial yield stress, Peric model is modified via introducing plastic strain to multiply the strain rate, for eliminating the effect of strain rate when the plastic strain is zero. Other constitutive models including the Wagoner, modified Hockett–Sherby and Peric are also considered and compared. The results show that the modified Peric model could not only describe the temperature-and rate-dependent flow stress, but also capture the rate-independent initial yield stress, while the Wagoner, modified Hockett–Sherby and Peric model can only describe the temperature-and rate-dependent flow stress. Moreover, the modified Peric model could obtain proper static yield stress more naturally, and this property may have potential applications in rate-dependent simulations.

The strain-rate sensitivity of the hardness in indentation creep

2007 ◽  
Vol 22 (4) ◽  
pp. 926-936 ◽  
Author(s):  
A.A. Elmustafa ◽  
S. Kose ◽  
D.S. Stone
Keyword(s):  
Flow Stress ◽  
Strain Rate ◽  
Strain Rate Sensitivity ◽  
Rate Sensitivity ◽  
Hertzian Contact ◽  
Indentation Creep ◽  
Proportionality Factor ◽  
Element Analysis ◽  
Elastic Deformations ◽  
The Relationship

Finite element analysis is used to simulate indentation creep experiments with a cone-shaped indenter. The purpose of the work is to help identify the relationship between the strain-rate sensitivity of the hardness, νH, and that of the flow stress, νσ in materials for which elastic deformations are significant. In general, νH differs from νσ, but the ratio νH/νσ is found to be a unique function of H/E* where H is the hardness and E* is the modulus relevant to Hertzian contact. νH/νσ approaches 1 for small H/E*, 0 for large H/E*, and is insensitive to work hardening. The trend in νH/νσ as a function of H/E* can be explained based on a generalized analysis of Tabor’s relation in which hardness is proportional to the flow stress H = k × σeff and in which the proportionality factor k is a function of σeff/E*.

Strain Rate Dependent Flow Stress and Energy Absorption Behaviour of Cast CrMnNi TRIP/TWIP Steels

2011 ◽  
Vol 82 (9) ◽  
pp. 1087-1093 ◽  
Author(s):  
L. Krüger ◽  
S. Wolf ◽  
S. Martin ◽  
U. Martin ◽  
A. Jahn ◽  
...  
Keyword(s):  
Flow Stress ◽  
Strain Rate ◽  
Energy Absorption ◽  
Rate Dependent ◽  
Twip Steels ◽  
Dependent Flow

scholarly journals Deformation Behavior and Dynamic Recrystallization of Mg-1Li-1Al Alloy

Metals ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 1696
Author(s):  
Xiaoyan Feng ◽  
Xue Pang ◽  
Xu He ◽  
Ruihong Li ◽  
Zili Jin ◽  
...  
Keyword(s):  
Flow Stress ◽  
Dynamic Recrystallization ◽  
Strain Rate ◽  
Volume Fraction ◽  
High Temperature Deformation ◽  
Temperature Deformation ◽  
Avrami Equation ◽  
Uniaxial Compression Test ◽  
Hot Workability ◽  
The Relationship

In this paper, the hot workability of Mg-1Li-1Al (LA11) alloy is assessed through a uniaxial compression test in a temperature range from 200 to 400 °C and a strain rate, έ, of 1–0.01 s−1. The present study reveals that flow stress increases when the strain rate increases and deformation temperature decreases. Based on the hyperbolic sine equation, the flow stress constitutive equation of this alloy under high-temperature deformation is established. The average activation energy was 116.5 kJ/mol. Avrami equation was employed to investigate the dynamic recrystallization (DRX). The DRX mechanism affected by the deformation conditions and Zener–Hollomon parameters is revealed. Finally, the relationship between DRX volume fraction and deformation parameter is verified based on microstructure evolution, which is consistent with the theoretical prediction.

Constitutive Modeling of the Rate-Dependent Behavior of Ti-6Al-4V Using an Arrhenius-Type Law

2012 ◽  
Vol 591-593 ◽  
pp. 949-954
Author(s):  
Jun Jie Xiao ◽  
Dong Sheng Li ◽  
Xiao Qiang Li ◽  
Chao Hai Jin ◽  
Chao Zhang
Keyword(s):  
Flow Stress ◽  
Strain Rate ◽  
Tensile Tests ◽  
Alloy Sheet ◽  
Uniaxial Tensile ◽  
Thin Wall ◽  
Rate Dependent ◽  
Hot Environment ◽  
Dependent Behavior ◽  
Element Simulation

Uniaxial tensile tests were performed on a Ti-6Al-4V alloy sheet over the temperature range of 923K-1023K with the strain rates of 5×10-4s-1-5×10-2s-1 up to a 25% length elongation of the specimen. The true stress-strain curves reveal that the flow stress decreases with the increase of the temperature and the decrease of the strain rate. In the same process, the accompanying softening role increases. It is found that the Ti-6Al-4V shows the features of non-linearity, temperature sensitivity and strain rate dependence in hot environment. Finally, an Arrhenius-type law has been established to predict the experimental data and the prediction precision was verified by the plotting of parameter and flow stress, which revealed that the error of stress exponent was only 4.99%. This indicates the flow stress model has high precision and can be used for the process design and the finite element simulation of hot forming thin-wall Ti-6Al-4V alloy components.

Strain-Rate-Dependent Flow Stress and Failure of an Mg-PSZ Reinforced TRIP Matrix Composite Produced by Spark Plasma Sintering

2012 ◽  
Vol 83 (6) ◽  
pp. 521-528 ◽  
Author(s):  
Sabine Decker ◽  
Lutz Krüger ◽  
Sarah Richter ◽  
Stefan Martin ◽  
Ulrich Martin
Keyword(s):  
Flow Stress ◽  
Strain Rate ◽  
Spark Plasma Sintering ◽  
Matrix Composite ◽  
Rate Dependent ◽  
Plasma Sintering ◽  
Spark Plasma ◽  
Dependent Flow

scholarly journals Strain Rate Dependent Flow Stress Characterization Using Piezo-actuated Micropress

2014 ◽  
Vol 81 ◽  
pp. 1451-1456 ◽  
Author(s):  
Muhammad Taureza ◽  
Sylvie Castagne ◽  
Tegoeh Tjahjowidodo ◽  
Peng Hu
Keyword(s):  
Flow Stress ◽  
Strain Rate ◽  
Rate Dependent ◽  
Dependent Flow

Research on Compressive Behavior and Deformation Heating of 7075-T6 Aluminum Alloy during Hot Compression

2014 ◽  
Vol 887-888 ◽  
pp. 315-318
Author(s):  
Dong Ge Wang ◽  
Rui Bin Mei ◽  
Ban Cai ◽  
Chun Li Zhang ◽  
Li Bao ◽  
...  
Keyword(s):  
Aluminum Alloy ◽  
Flow Stress ◽  
Strain Rate ◽  
Temperature Rise ◽  
Strain Rate Range ◽  
Hot Compression ◽  
Deformation Heating ◽  
Deformation Velocity ◽  
Fluctuation Range ◽  
The Relationship

The flow stress behavior of the 7075-T6 aluminum alloy was studied through single-pass compression experiment by using MMS-300 simulator within temperature range of 300-450°C and strain rate range of 0.01-40s-1. Then a simulation of compression was carried out and the influence of deformation velocity on load and deformation heating was investigated according to the relationship between stress and strain. The results show that dynamic recrystallization occurs in hot compression of 7075-T6 alloy and the stress-strain curves are presented as wave. Furthermore, the flow stress curves have the same wave period and the fluctuation range increases with an increase of strain rate and a decrease of strain. Increasing of deformation velocity results in higher critical strain but the value decreases when the deformation velocity is much higher. The temperature rise increases with the increase of deformation velocity and decrease of deformation temperature. The maximum of temperature rise is more than about 30°C, so that the deformation heating is significant.

Sign in / Sign up

Export Citation Format

Share Document