Engineering Commons^™

Sputtering Power Effects On Growth And Mechanical Properties Of Cr2alc Max Phase Coatings, Muhammad Naveed, Aleksei Obrosov, Andrzej Zak, Wlodzimierz Dudzinski, Alex A. Volinsky, Sabine Weiß

Mechanical Engineering Faculty Publications

Coating growth and mechanical properties of nanolamellar Cr₂AlC coatings at various sputtering power were investigated in the present study. Cr₂AlC coating was deposited on the IN 718 superalloy and (100) Si wafers by DC magnetron sputtering at different sputtering powers. The structure and properties were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and nanoindentation. It was found that coatings had columnar structure with nanocrystalline substructure. Deposition rate increased with the sputtering power. XRD results showed the presence of the Cr₂AlC MAX phase, intermetallic AlCr₂ and Cr_{7 …}

Study On Mechanical Properties Of Silicone Rubber Materials Used As Gaskets In Pem Fuel Cell Environment, Guo Li

The 8th International Conference on Physical and Numerical Simulation of Materials Processing

No abstract provided.

Effect Of Ti Content On Microstructure And Strength Of The Self-Joining Of Zrb2–Sic With Pd–Co–Ti Filler Metals, Jie Zhang, Jiayin Liu, Chungfeng Liu, Tianpeng Wang

The 8th International Conference on Physical and Numerical Simulation of Materials Processing

No abstract provided.

Influence Of Pre-Stretching On The Subsequent Creep Aging Behavior Of Aluminum Alloy 2524, Yongqian Xu, Lihua Zhan, Minghui Huang, Youliang Yang

The 8th International Conference on Physical and Numerical Simulation of Materials Processing

No abstract provided.

Low-Temperature Bainite Transformation Behavior And Microstructure And Mechanical Properties Of A Medium-Carbon High-Strength Steel For Railway Forging Upper Core Plate, Xiaofeng Qin, Shihai Cui, An Wang

The 8th International Conference on Physical and Numerical Simulation of Materials Processing

No abstract provided.

Properties That Characterize The Material X46cr13 Steel, Josip Brnic, Sanjin Krscanski, Marino Brcic, Jitai Niu

The 8th International Conference on Physical and Numerical Simulation of Materials Processing

No abstract provided.

Mechanical Properties Of Stainless Steels With Heterogeneous Nanostructures, Hiromi Miura, Masakazu Kobayashi, Natuko Sugiura, Naoki Yoshinaga

The 8th International Conference on Physical and Numerical Simulation of Materials Processing

No abstract provided.

Effect Of Ni Content And Brazing Temperature On The Self Joining Of Zrb2–Sic, Jiayin Liu, Jie Zhang, Chunfeng Liu, Tianpeng Wang

The 8th International Conference on Physical and Numerical Simulation of Materials Processing

No abstract provided.

Slm Processing-Microstructure-Mechanical Property Correlation In An Aluminum Alloy Produced By Additive Manufacturing, Bryce Abstetar

Graduate Theses & Non-Theses

Additive manufacturing has become a highly researched topic in recent years all over the world. The current research evaluates the merits of additive manufacturing based on the mechanical, microstructural, and fracture properties of additive manufactured AlSi10Mg test specimens. The additive manufactured build plates consisted of tensile and fatigue test specimens. They were printed in the 0°, 30°, 60°, and 90° orientations relative to the build platform. Tensile and dynamic fatigue tests were conducted followed by microstructural characterization and fracture analysis. A wrought 6061 T6 aluminum alloy was also tested for comparison. Tensile tests revealed similar ultimate tensile strengths for all …

Γ/Γ' Co-Base Superalloys – New High Temperature Materials Beyond Ni-Base Superalloys?, Steffen Neumeier, Christopher H. Zenk, Lisa P. Freund, Mathias Göken

Beyond Nickel-Based Superalloys II

In 2006 a new L1₂ phase, Co₃(Al,W), was discovered in the Co-Al-W system which has led to the development of novel Co-base superalloys with g/g¢ microstructures similar to those of the well-established Ni-base superalloys. First investigations on simple ternary alloys could show that these Co-Al-W based alloys exhibit higher solidus temperatures and show less segregations after casting compared to typical Ni-base superalloys. This leads to the question whether this g/g¢ Co-base superalloys can be regarded as new class of high temperature materials that can compete with or even supersede established Ni-base superalloys.

In the first part of …

Effect Of Original Layer Thicknesses On The Interface Bonding And Mechanical Properties Of Ti-Al Laminate Composites, Minyu Fan, Joseph P. Domblesky, Kai Jin, Liang Qin, Shengqiang Cui, Xunzhong Guo, Naksoo Kim, Jie Tao

Mechanical Engineering Faculty Research and Publications

It is of great significance in high-temperature aeroengine applications for large-surface-area TiAl laminate composites to be fabricated into Ti-Al₃Ti parts by plastic forming and subsequent vacuum hot pressing. Then the original layer thicknesses have an important influence on the interface bonding and mechanical properties of TiAl laminate composites, but only few reports about it have been published so far. In the present study, vacuum hot pressing was employed to fabricate TiAl laminate composites using Ti and Al foils of different thickness. The resulting interface bond and mechanical properties of TiAl laminate composites were then studied to determine the …

Effect Of Nano-Sio2 Content On The Setting Time And Mechanical Properties Of Tricalcium Silicate, Zhenhai Xu, Zonghui Zhou, Xin Cheng

International Conference on Durability of Concrete Structures

Using analytically pure calcium carbonate and silica as raw materials, high purity tricalcium silicate (C₃S) is prepared by solid-state reaction. The tricalcium silicate was sintered at a temperature of 1550°C with the heat preservation time of 6 h. The final sample needs three times of calcination circles. Ultrasonic cleaning machine was used to disperse the water and different amount of nano-SiO₂ (0, 1, 2, and 3 wt%) for 5 min, then mixed with C₃S, and formed into standard blocks. The setting time and compressive strength of each age (1, 3, 7, and 28 days) was …

Mechanical And Electrical Characterization Of Carbon Nanofibers Produced From Water Soluble Precursors, Lee D. Cremar, Javier Acosta-Martinez, Alexsandra Villarreal, Alfonso Salinas, Karen Lozano

Mechanical Engineering Faculty Publications and Presentations

This study presents the thermo-physical, electrical, and mechanical characterization of fine carbon fibers produced from water-soluble polymer precursors and low temperature processes. These fibers were developed utilizing the Forcespinning® technology which utilizes centrifugal force to spin fibers. Polyvinyl alcohol was used as the precursor material, and fibers were developed and deposited in a non-woven configuration. The resultant non-woven fiber mats were subjected to a dehydration process through exposure to sulfuric acid vapors. The partially carbonized mats were heat treated at 850 °C. The produced porous nonwoven carbon fiber based mats have micro-and mesoporosity with a final fiber average diameter of …

Effect Of Cooling Rate During Solution Heat Treatment On The Microstructure And Mechanical Properties Of Sp-700 Titanium Alloys, Jo-Kuang Nieh, Chih-Ting Wu, Yen-Lin Chen, Chao-Nan Wei, Sheng-Long Lee

Journal of Marine Science and Technology

The relationship between the microstructures and the mechanical properties of solution-treated SP-700 titanium alloys, as obtained with different cooling rates, was investigated. The results indicate that the water-quenched alloy contains the primary  (p), ”-martensite and residual  (r) phases. Aging heat treatment can convert both ”-martensite and the r phases to the fine-grained  +  equilibrium phases, resulting in a significant increase in tensile strength and hardness. Both the air-cooled and furnace-cooled alloys consist of the p,  and  phases. The air-cooled alloy containing the fine-grained  phase has relatively higher hardness. Aging heat treatment causes only …

Modified Yttrium Hydroxide/Mc Nylon Nanocomposites And Scaling Effects In Multilayer Polyethylene Films, Jia Chen

USF Tampa Graduate Theses and Dissertations

In this thesis, monomer casting (MC) nylon was synthesized. MC nylon could replace nonferrous metals in certain applications, including gears, wheels, and other moving parts. However, compared with metals, MC nylon products have poor strength and stiffness, and crack easily, especially at low temperatures. In addition, the dimensional stability of MC nylon is poor, especially in the large casting nylon products, causing significant internal stresses due to shrinkage. Thus, MC nylon cracks easily when cast and molded. The yttrium hydroxide particles were modified by stearic acid and dispersed in the caprolactam. The polymerization time was short due to fast anionic …

Engineering Of Lightweight Ceramic Composites By Spark Plasma Sintering, Oleg Vasylkiv

Electric Field Assisted Sintering and Related Phenomena Far From Equilibrium

It is well recognised that value of porosity and grain size influences mechanical properties such as fracture toughness, elastic modulus and strength dramatically. Boron carbide (B₄C), as well as other lightweight ceramics like TiB₂, B₆O requires high consolidation temperatures owing to its poor sinterability. Therefore such decrease of ceramics properties becomes a materials processing issue since during consolidation process on the final stage of sintering (either pressure-assisted or pressureless one) grain growth starts. To overcome this problem, various metallic and non-metallic binders are used to obtain dense borides. However, the presence of a metallic …

Improving The Capacity, Durability And Stability Of Lithium-Ion Batteries By Interphase Engineering, Qinglin Zhang

Theses and Dissertations--Chemical and Materials Engineering

This dissertation is focus on the study of solid-electrolyte interphases (SEIs) on advanced lithium ion battery (LIB) anodes. The purposes of this dissertation are to a) develop a methodology to study the properties of SEIs; and b) provide guidelines for designing engineered SEIs. The general knowledge gained through this research will be beneficial for the entire battery research community.

Influence Of Nb On The Β → Α″ Martensitic Phase Transformation And Properties Of The Newly Designed Ti-Fe-Nb Alloys, Shima Ehtemam-Haghighi, Yujing Liu, Guanghui Cao, Lai-Chang Zhang

Research outputs 2014 to 2021

A series of Ti-7Fe-xNb (x = 0, 1, 4, 6, 9, 11 wt.%) alloys was designed and cast to investigate the β → α″ martensitic phase transformation, β phase stability, the resulting microstructure and mechanical properties. Phase analysis revealed that only Ti-7Fe-11Nb alloy shows a single body-centred cubic β phase microstructure while the others are comprised of β and orthorhombic α″ phases. Moreover, Nb addition up to 11 wt.% enhances the stability and volume fraction of β phase in the microstructure, hence reducing the propensity of the alloy system to form α″ phase during quenching. Compressive yield strength and hardness …

The Heat Treatment Analysis Of E110 Case Hardening Steel, Majid Tolouei Rad, Eric Lichter

Research outputs 2014 to 2021

This paper investigates mechanical and microstructural behaviour of E110 case hardening steel when subjected to different heat treatment processes includingquenching, normalizing and tempering. After heat treatment samples were subjected to mechanical and metallographic analysisand the properties obtained from applying different processes were analysed. The heat treatment process had certain effects on the resultant properties andmicrostructures obtained for E110 steel which are described in details. Quenching produced a martensitic microstructure characterized by significant increase in material’s hardness and a significant decreased in its impact energy. Annealed specimens produced a coarse pearlitic microstructure with minimal variation in hardness and impact energy. For …

Equiaxed Ti-Based Composites With High Strength And Large Plasticity Prepared By Sintering And Crystallizing Amorphous Powder, Lehua Liu, Chao Yang, L. M. Kang, Yan Long, Zhiyu Xiao, Peijie Li, Laichang Zhang

Research outputs 2014 to 2021

High-performance titanium alloys with an equiaxed composite microstructure were achieved by sintering and crystallizing amorphous powder. By introducing a second phase in a β-Ti matrix, series of optimized Ti-Nb-Fe-Co-Al and Ti-Nb-Cu-Ni-Al composites, which have a microstructure composed of ultrafine-grained and equiaxed CoTi₂ or (Cu,Ni)Ti₂ precipitated phases surrounded by a ductile β-Ti matrix, were fabricated by sintering and crystallizing mechanically alloyed amorphous powder. The as-fabricated composites exhibit ultra-high ultimate compressive strength of 2585MPa and extremely large compressive plastic strain of around 40%, which are greater than the corresponding ones for most titanium alloys. In contrast, the alloy fabricated by …

Characterization Of Fibrin Matrix Incorporated Electrospun Polycaprolactone Scaffold, Cho Yi Wong

Theses and Dissertations

Specific objective: Guided tissue regeneration (GTR) aims to regenerate the lost attachment apparatus caused by periodontal disease through the use of a barrier membrane. For the GTR procedures to be successful, barrier membranes are required to be present at the surgical site for an extended period of time (weeks to months). Synthetic membranes have the advantage of prolonged presence in a wound site; however, they do not actively contribute to wound healing. Biologic membranes are recognized by the host tissue and participate in wound healing but have the disadvantage of early resorption. Therefore, the goal of this study is …