麻豆成人91精品二区三区

We generate reliable fatigue and fracture data to help engineers design safer components. Our team specializes in coupon-level testing, analysis, and modeling for metals, thermoplastics, and carbon-fiber reinforced polymers including FFF/AM materials. We partner with industry and agencies to turn rigorous experiments into actionable S鈥揘/蔚鈥揘 curves, design allowables, and failure insights.   Research Area:

• Fatigue & Fracture Mechanics
  Advanced concepts in fatigue behavior, fracture mechanics, and life prediction with applications in structural design.
  
  
• Additive Manufacturing for Mechanical Engineers
  Fundamentals of design for additive manufacturing, processes, and structural performance of additively manufactured metals, polymers and composites.
  
  
• Machine Design Components
  Principles of mechanical component design, stress/strain analysis, and reliability under static and fatigue loading.
  
  
• Finite Element Analysis (FEA)
  Introduction to computational modeling, stress analysis, and design optimization using commercial FEA software.
  
  

• Composite Materials
  Study of fiber- and particle-reinforced materials, including mechanical behavior, micromechanics, failure modes, and applications in aerospace, automotive, and biomedical fields.

Lab Director: Mohammad Amjadi, Ph.D., P.E. Assistant Professor of Mechanical Engineering   麻豆成人91精品二区三区  1811 North Boulder Ave.   Corley 222  Russellville, AR 72801  Phone: 479-964-0583, Ext. 4204 Email: mamjadi@atu.edu
Former Students:  Brayden May (Currently Tooling and Process Engineer at ) Brayden May is undergraduate alumni, majoring in Mechanical Engineering. His research focused on the fatigue behavior of 3D-printed thermoplastics, contributing to advancements in additive manufacturing techniques and material durability testing.
Minh Tran (Currently Development Engineer at First Solar) Minh Tran is a Mechanical Engineering graduate student doing research on fatigue behavior of porous titanium and thermoplastic cellular structures. Minh's research aims to enhance the performance and durability of materials used in advanced engineering applications. In addition to his academic work, Minh gained valuable industry experience during a summer internship at AESC US headquarters in Smyrna, Tennessee. As an electric vehicle (EV) and energy storage systems (ESS) battery cell process engineer intern, Minh developed an automated packaging machine capable of processing 15 battery cells per minute, improving efficiency and safety.
Genya Ohama: A Bachelor's student majoring in Mechanical Engineering at 麻豆成人91精品二区三区, conducted fatigue testing experiments on 17-4 Stainless Steel material produced by binder jetting.

 

Service

Standards-Aligned Methods (e.g., ASTM E466 axial fatigue, ASTM E606 strain-controlled fatigue; ASTM D7791-style methods for polymers/composites where applicable) MONOTONIC TESION TESTING Determine elastic modulus, 0.2% offset yield strength, ultimate tensile strength, fracture stress, total elongation, and ductility. FATIGUE TESTING Measure life under cyclic loading to develop S鈥揘 or 蔚鈥揘 curves, endurance limits, and mean-stress/frequency effects for design allowables. FRACTURE TOUGHNESS TESTING Fracture Toughness Testing provides information about a material鈥檚 resistance to crack extension under a steadily increasing load. FATIGUIE CRACK GROWTH TESTING Measure crack-growth kinetics under cyclic loading (da/dN vs. 螖K or 螖J) to support life prediction and damage-tolerance analysis. HARDNESS TEST Indentation-based assessment of strength and wear resistance (methods selected per material; e.g., Rockwell, Vickers, or Shore). FRACTOGRAPHY Examine fracture surfaces to locate initiation sites and identify failure mechanisms (e.g., ductile tearing, brittle cleavage, fatigue striations) for root-cause analysis.

 

EQUIPMENT

 

1. Servopulser Servo Dynamic Systems EHF-E SERVOPULSER, 50KN, 卤 50 mm from Shimadzu     Features include: Up to 卤50 kN axial force capacity GRIP SET, SPLIT FLANGE, 50KN Crack growth and fracture toughness grip set and sensor Wide range of grips, fixtures, and accessories
3. Axial Extensometers  For different specimen sizes: Epsilon-Model 3542 Epsilon-Miniature Axial Extensometers 鈥� Model 3442
3. Rotating Bending
4. Optical Microscopy
5. Hardness Tester
6. Infrared Camera

 

Academic Partners:  Iowa State University  Auburn University University of Arkansas for Medical Sciences, Biomechanics lab Orgnizational Partners:  ASTM F42 Committee on Additive Manufacturing Technologies (Polymers) ICAM Scientific Organizing Committee (Polymers) Collaborative Working Group (CWG)

Journal Publications:

1. Dyer, K., Amjadi, M., Shao, S., Shamsaei, N., & Molaei, R., "". Additive Manufacturing, 2025, 104966. .
2. Amjadi, M.; Fatemi, A.,鈥� 鈥�. Composites Part A: Applied Science and Manufacturing, 2024. 180: p. 108050.
3. Amjadi, M.; Fatemi, A.,鈥� A Fatigue Damage Model for Life Prediction of Injection Molded Short Fiber Reinforced Thermoplastic Composites鈥�. Polymers. 2021, 13, 2250. 
4. Amjadi, M.; Fatemi, A.,鈥漈ensile Behavior of High-Density Polyethylene Including the Effects of Processing Technique, Thickness, Temperature, and Strain Rate鈥�. Polymers 2020, 12, 1857. 
5. Amjadi, M.; Fatemi, A.,鈥� Creep and fatigue behaviors of High-Density Polyethylene (HDPE): Effects of temperature, mean stress, frequency, and processing technique鈥�. International Journal of Fatigue. 2020; 141: 105871. doi: 10.1016/j.ijfatigue.2020.105871.
6. Amjadi, M.; Fatemi, A. Creep behavior and modeling of high-density polyethylene (HDPE). Polymer Testing 2021, 94, 107031, doi: 10.1016/j.polymertesting.2020.107031.
7. Amjadi, M.; Fatemi, A.,鈥� Multiaxial Fatigue Behavior of Thermoplastics Including Mean Stress and Notch Effects: Experiments and Modeling鈥�. International Journal of Fatigue. 2020; 136: 105571. doi: 10.1016/j.ijfatigue.2020.105571.
8. Amjadi, M.; Fatemi, A.,鈥� Multiaxial Fatigue Behavior of High-Density Polyethylene (HDPE) Including Notch Effect: Experiments and Modeling鈥�. ICMFF12 - 12th International Conference on Multiaxial Fatigue and Fracture; MATEC Web of Conferences. 2019; 300: 05001. doi: 10.1051/matecconf/201930005001.
9. Amjadi M, Nikkhoo M, Khalaf K, et al., 鈥淎n in silico parametric model of vertebrae trabecular bone based on density and microstructural parameters to assess risk of fracture in osteoporosis鈥�. Proceedings of the Institution of Mechanical Engineers, Part H: Journal of Engineering in Medicine. 2014;228(12):1281-1295. doi:10.1177/0954411914563363.

 

Conferences: 

1. Amjadi, M, Brayden May, Genya Ohama, and Minh Hoang Tran; 鈥淔atigue Behavior of Additively Manufactured PA6-GF TPMS Structures using FDM鈥�, the ASTM International Conference on Advanced Manufacturing, Atlanta, GA, 2024.
2. Molaei, R, Amjadi, M; 鈥淔atigue Behavior of Additively Manufactured Titanium TPMS Structures using Selective Laser Melting鈥�, the ASTM International Conference on Advanced Manufacturing, Atlanta, GA, 2024.
3. Amjadi, M; Molaei, R, 鈥淎 Comparison between Additive Manufacturing and Injection Molding Techniques鈥�, the ASTM International Conference on Advanced Manufacturing, Washington, DC, 2023.
4. Amjadi, M.; Fatemi, A.,鈥� A Critical Plane Fatigue Damage Model for Multiaxial Fatigue Life Prediction of Injection MoldedShort Fiber Reinforced Thermoplastic Composites鈥�. 13th International Conference on Multiaxial Fatigue and Fracture (ICMFF13), New Orleans, LA, USA, 2022.
5. Amjadi M, Fatemi A., 鈥淢ultiaxial Fatigue Behavior of Thermoplastics; Experimental Study and Modeling鈥�. New trends in fatigue and fracture - NT2F19, Tucson, Arizona, USA, 2019.
6. Amjadi, M.; Fatemi, "Fatigue Behavior of High-Density Polyethylene: Effects of Temperature, Mean Stress, and Manufacturing Method," 12th International Fatigue Congress (FATIGUE 2018), Poitiers Futuroscope-France, May 2018.

1. Promoting Electric Propulsion鈥� (PEP) boat races: 

• PEP 2025:
• PEP 2024:

Read more about Arkansas Tech Engineeering Team at PEP Competition here:  

 Sponsered by American Society of Naval Engineers.