Engineering Commons^™

Analysis Of A University Bike-Sharing Program And Lessons Learned, Margaret Mcnamara, Jijo K. Mathew

Purdue Road School

Purdue University initiated a bike-sharing program in August 2015 with 13 locations and 50 bikes. The first 14 weeks of the program saw 15,259 rentals for a total of 22,677 hours. The Purdue sustainable transportation staff partnered with Purdue traffic engineering students to monitor usage trends to identify future investment opportunities and changes to the bike sharing contract. In this session we will present the series of analytics performance measures, management dashboards, and changes initiated as a result of this partnership.

Full Depth Reclamation Of Aviation Pavement, Michael W. Buening

Purdue Road School

Full depth reclamation (FDR) has been utilized multiple times in recent years for airport and roadway pavement rehabilitation. The presentation will review FDR and its use as a treatment for aviation pavements.

Effective Roadway Management Of Septic Systems & Wells, Michael M. Gavelek, Denise H. Wright, Matthew Witt

Purdue Road School

Roadway construction in rural & urban fringe regions impacts properties that utilize septic systems & wells. Due to their fundamental difference from centralized utilities, they can fall through the cracks & create critical path problems & unforeseen costs. Decentralized water & wastewater experts will present engineering fundamentals, construction techniques & costs, regulations & regulatory process, and tips to effectively manage the replacement & protection of septic systems & wells.

Indot Signing - Recent Developments For Attraction Signs, Joseph Bruno

Purdue Road School

Summary of INDOT's policy on attraction signing and tips for addressing attraction signs in design plan development for INDOT road projects. Presented at Purdue University Road School on March 9, 2016.

Fhwa Compliance:Results And Responses For 2015/ 2016, Jay Dumontelle, Eryn Fletcher

Purdue Road School

This presentation discuss the results from the FHWA's 2015 Compliance Assessment Program and explains how these results are being used to direct the FHWA's activities in 2016.

Traffic Ticker, Margaret Mcnamara

Purdue Road School

The Traffic Ticker is a web-based tool developed for use by INDOT to monitor interstate conditions in real-time. Based in crowdsourced probe vehicle data, it is linked to a variety of other tools to provide powerful monitoring and after action review capability. The advantages of this tool are demonstrated in case studies spanning winter operations, interstate crashes, and the I-65 N detour route in August 2015.

Design, Operations, And Safety Of High-Speed Approach Rural Roundabouts, David A. Church, James Tobaben

Purdue Road School

High-speed approach rural roundabouts have been found to reduce overall crashes by 71% and injury crashes by 87% and have become an effective tool used by public agencies to improve safety and capacity at rural intersections. In this presentation we will discuss critical design features for effective implementation, including alignment on approach, deflection, splitter islands, lighting, signing, curbing, diameter, design vehicle, and landscaping. Before-and-after results involving safety, operations, and public acceptance will be highlighted at specific US roundabouts.

Ada And Title Vi: Remaining Eligible For Funding, Cathy Gross

Purdue Road School

Learn how to effectively implement ADA and Title VI nondiscrimination and accessibility requirements in your community to become and remain compliant and eligible for federal funds. In this session we will present changes to the law and requirements effective in 2015 and beyond. You will learn what resources are available to get and keep your community on track and find out how several Indiana communities are making strides in ADA and Title VI compliance.

Americans With Disabilities Act And Curb Ramps, Katherine Smutzer

Purdue Road School

INDOT is in the process of adopting the Public Right of Way Accessibility Guidelines (PROWAG) for pedestrian access route design within public right of way. Updates to the Indiana Design Manual and Standard Drawings will be presented and discussed, including revisions anticipated in 2016 to the curb ramp standard drawings and pedestrian signal placement standards. This presentation will include information from the INDOT standards section and INDOT ADA committee.

Generating Mgal2o4 Whiskers Using Carbothermic Reactions And Sps/Fast, Anton Salomon

Electric Field Assisted Sintering and Related Phenomena Far From Equilibrium

The study is focussed on the rapid generation of whisker-like magnesia-aluminate spinel (MgAl₂O₄) crystals. Two recently developed carbon-bonded refractory ceramics, pyrolyzed MgO-C and Al₂O₃-C [1], were used as the starting materials. The heating to 1600 °C was performed in a SPS/FAST device to facilitate carbothermic reactions, which resulted in the reduction of the specific oxide and the subsequent nucleation and growth of fibre-like crystals.

The research was based on a recently published study [2] that had established the possibility of the MgAl₂O₄ whisker formation in a composite structure consisting …

Discoloration Of Spark–Plasma–Sintered Transparent Mgal2o4 Spinel, Koji Morita

Electric Field Assisted Sintering and Related Phenomena Far From Equilibrium

It is reported that the spark-plasma-sintered (SPSed) transparent oxides exhibit a discoloration. The discoloration is known to be more remarkable in the SPSed oxides than the HIP/HP processed ones. In order to understand the discoloration phenomena, the discoloration was investigated by spectroscopic techniques using a spinel (MgAl₂O₄) as the reference material.

The discoloration is explained by the combination of carbon contaminations and lattice defects (color centers), which are introduced in the spinel matrix depending on the SPS conditions. For high heating rate of ³50°C/min, carbon contamination occurred by evaporating the carbon phases from the carbon papers …

Exploring Length Scale–Property Relationships In Dense Nanocrystalline Materials, Javier Garay

Electric Field Assisted Sintering and Related Phenomena Far From Equilibrium

The influence of nano-scale defects (grain/phase boundaries, pores, etc) can be significantly different from micro-scale features. We will discuss how interfaces in nanocrystalline materials interact with light (phonons) and heat (phonons) and how precise control of these defects can be used to tune materials properties. We will start by discussing how current activated pressure assisted densification (CAPAD) can be leveraged to produce dense nanocrystalline samples by effectively overcoming the grain growth challenge. In particular the effect of the relevant processing parameters, pressure, time and temperature on grain sizes will be presented and density will be presented. We will present experimental …

Electrical Field Effects In Spark Plasma Sintering Of Hyperstoichiometric Uo2, Marco Cologna

Electric Field Assisted Sintering and Related Phenomena Far From Equilibrium

Recent research in the field assisted sintering of actinide oxides and nitrides has shown the great potential of the technique, but has also evidenced the need for a better understanding of the behavior of such class of materials during processing with current/fields [1-3]. Uranium dioxide, due to its multiple oxidation states and semiconductor characteristic, represents a good model material to investigate some of the peculiar effects of the electric field in the processing of materials. The stoichiometry of UO₂ is of paramount importance, since it governs its fundamental properties, such as the thermal and electrical conductivity, the diffusion coefficients …

Development Of Electric Current Activated/Assisted Sintering (Ecas/Sps), Salvatore Grasso

Electric Field Assisted Sintering and Related Phenomena Far From Equilibrium

The electric current activated/assisted sintering (ECAS) is an ever growing class of versatile techniques for sintering particulate materials. ECAS was pioneered by Bloxam in 1906. As illustrated in Fig. 1, ECAS development is emblematic of its technological and scientific importance. Nowadays, most of the scientific attention is focused on the Spark Plasma Sintering (SPS) technology originated in 1966 by Dr. Inoue [1].

Essentially, SPS exploits the same punch/die system concept as the more familiar hot pressing (HP) process. The powder is placed in the die and subsequently pressed between two counter-sliding punches. Mechanical loading is normally uniaxial. SPS and HP …

Ceramics Of Potassium Sodium Niobate By Field–Assisted Sintering Techniques: Spark Plasma Sintering Versus Spark Plasma Texturing, Paula Maria Vilarinho

Electric Field Assisted Sintering and Related Phenomena Far From Equilibrium

Potassium sodium niobate (KNN) is one of the most promising lead-free systems. However, undoped KNN has poor sinterability and by conventional sintering results in inadequate densification and, consequently, in inferior physical and electrical properties. The highly volatile alkaline sodium and potassium do not permit the increase of the sintering temperature somehow required to densify the niobium based ceramics. This conflict can be solved if the mass transport during the sintering step is enhanced, since the temperature and time needed for consolidation must be reduced in order to avoid volatilization. Among the methods reported for activation of the mass transport during …

Benefits Of Sps Sintering On Microstructure And Piezoelectric Properties Of Knn–Based Ceramics, Florian Jean

Electric Field Assisted Sintering and Related Phenomena Far From Equilibrium

PZT and its derivatives exhibit a wide range of piezoelectric properties allowing their applications in transducers, actuators and sensors. However, due to the toxicity of lead for human health and environment, many studies are carried out on lead-free piezoelectric materials. Among these materials, (K,Na)NbO₃ (KNN)-based solid solutions seem to be promising candidates owing to their high dielectric, piezoelectric and mechanical characteristics shown by Saito et al. in 2004. However, reaching high density for these materials appears difficult and alkali volatilization may occur during sintering process. In order to overcome these difficulties, in the present work, K_0.5Na_{0.5 …}

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 …

Electric Current As A Driving Force For Interphase Growth In Spark Plasma Sintered Dielectric Composites, Catherine Elissalde

Electric Field Assisted Sintering and Related Phenomena Far From Equilibrium

All-oxide composites are increasingly investigated in the field of microelectronics and telecommunications because of their multi-functionalities. Dielectric properties can be tuned in ferroelectric-based composites performed by Spark plasma sintering (SPS) through a control of composition, grain size, architecture and charged defects at interfaces. Using SPS on ceramic bilayers made of ferroelectric Ba_0.65Sr_0.35TiO₃ (BST65/35) and TiO₂ dielectric phases, we show that the reactivity at their interfaces is dependent on the direction of the current and/or on the sintering temperature. The electric current promotes an interphase growth whose thickness depends on the bilayer stacking and on …

Low–Temperature Spark Plasma Sintering Of Transparent Ceramics By Using Sic Molding Set, Byung-Nam Kim

Electric Field Assisted Sintering and Related Phenomena Far From Equilibrium

Hydroxyapatite (HAP) and alumina ceramics were sintered at low temperatures by using the SiC molding set during spark plasma sintering (SPS). Transparent ceramics were obtained at 800 ˚C and 1000 ˚C for HAP and alumina, respectively. The SiC is electrically conductive (3x10⁴ S/m), so that the molding set (mold, punch and spacer) was directly heated during SPS without external heating. Compared to the conventional graphite molding set, the voltage level during heating was higher due to lower conductivity. When the graphite molding set was used, the temperature required for transparent HAP and alumina was about 950 ˚C and 1150 …

Microscopic Densification Mechanisms Of Metallic Systems By Spark Plasma Sintering, Jean Philippe Monchoux

Electric Field Assisted Sintering and Related Phenomena Far From Equilibrium

This study reports on the microscopic mechanisms accounting for the fast densification kinetics of metallic materials processed by spark plasma sintering (SPS). Metallic systems have been chosen in reason of their elevated electric conductivity. Hence, an important fraction of the electric current of the SPS passes through the powder, and electrically induced new mechanisms, or acceleration of conventional ones (e.g. plasticity, diffusion), can be expected. TiAl powder and Ag-Zn diffusion couple have thus been chosen to study the influence of the electric current on plasticity and on diffusion, respectively.

An originality of this work was to observe by transmission electron …

Sps For Chemical Preparations, Ihor Veremchuk

Electric Field Assisted Sintering and Related Phenomena Far From Equilibrium

The Spark Plasma Sintering (SPS) has been developed for shaping materials by combining simultaneously uniaxial pressure (using direct contact with the sample) and the application of an direct electric field. Even though the key mechanisms controlling SPS are still debated, this technique shows a number of advantages – (i) reduction of sintering time, (ii) rapid densification and (iii) grain growth suspension – which are helpful for tailoring the microstructure of functional materials and thus optimize their electronic transport, mechanical and/or thermal properties.

The diffusion rate of SPS conditions was reported to become extremely large at relative low temperatures due to …

The Influence Of Doping On Flash Sintering Condition In Srti1–Xfexo3–Δ, Neta Shomrat

Electric Field Assisted Sintering and Related Phenomena Far From Equilibrium

The innovative flash sintering process raised a great interest in the past few years due to its applicability in various engineering fields and the interesting scientific questions it evokes. This technique could be beneficial in many applications since it reduces the time and cost of the sintering process. Joule heating can explain the sudden temperature rise of the sample, which enhances the rate of grain boundary diffusion. However, for a given material the temperature of the sample remains lower than the temperature at conventional sintering. Although Joule heating is a significant phenomenon, it is proposed that lattice defects and their …

Flash Sintering Of Glass Containing Alumina Bodies, Mattia Biesuz

Electric Field Assisted Sintering and Related Phenomena Far From Equilibrium

Flash sintering of glass containing alumina bodies

Development Research And Implications For Cte, Jeff M. Shannon

Morehead State Theses and Dissertations

A capstone submitted in partial fulfillment of the requirements for the degree of Doctor of Education in the College of Education at Morehead State University By Jeff M. Shannon on March 9, 2016.

The Mechanisms Of Field Assisted Sintering In Metallic Systems, Johannes Trapp

Electric Field Assisted Sintering and Related Phenomena Far From Equilibrium

Using the advantages of Spark Plasma Sintering to produce superior materials, e.g. with potentially new phases, first requires a profound understanding of the densification mechanisms that are active during the process. The research presented contributes to this understanding by connecting temperature and pressure distribution in the particles with rate and activation energy of densification in pure copper.

Activation energy (Q) has been determined using a method originally developed by J. E. Dorn. Therewith, the activation energy for diffusion controlled processes can be extracted from densification rate measurements without the results being influenced by errors in measuring the density of the …

Effect Of Turbulence And Roughness On Coupled Porous-Medium/Free-Flow Exchange Processes, Thomas Fetzer, Kathleen M. Smits, Rainer Helmig

Civil Engineering Faculty Publications - Archive

The interactions between turbulent free flow and flow in a porous medium are of key interest in different fields, e.g., meteorology, agriculture, building physics, and aerospace engineering. Properly understanding the strongly coupled exchange processes between the two domains is crucial to describing these interactions. In (Mosthaf et al. in Water Resources Research 47(10):W10522, 2011. doi:10.1029/2011WR010685), a concept for coupling laminar compositional single-phase free flow to compositional two-phase porous-medium flow under non-isothermal conditions was presented. In this study, the existing coupling concept is first extended to turbulent free-flow conditions. This includes the interface conditions between a Reynolds-averaged Navier–Stokes free flow using …

Electric Field Effects On Grain Boundary Formation And Grain Growth, Klaus Van Benthem, Hasti Majidi, Jorgen Rufner, Wei Qin

Electric Field Assisted Sintering and Related Phenomena Far From Equilibrium

The application of electric fields can enable the accelerated consolidation of materials during field assisted sintering, such as spark plasma sintering or flash sintering. Although such techniques are already employed for the synthesis of a wide variety of microstructures with unique macroscopic properties, a fundamental understanding of the atomic-scale mechanisms for grain boundary formation and subsequent migration in the presence of electrostatic potentials is mostly absent from the literature. We have designed experiments to specifically de-couple the effects of heating and applied electrostatic fields during consolidation. In situ transmission electron microscopy studies were carried out with new sample holder designs …

Evolve Mentor Program, Sheryl M. Proctor, Timothy Wells, Ed Cox, Indiana Department Of Transportation

Purdue Road School

This is a presentation of the EVOLVE mentor program at the Indiana Department of Transportation which shows a model of linking talent strategy to business strategy. This started as a pilot program for Engineers-in-Training who expressed a desire for mentorship and career guidance. The program included 1:1 mentor/mentee pairings as well as group mentoring.

Wildcat Bridge - I-65 Artesion Well/Geotechnical/Structural, Anne Rearick, Jeremy Hunter, Silas Nichols, Mir Zaheer

Purdue Road School

In this session we will discuss the emergency design and repair of the I-65 bridge over Wildcat Creek in Tippecanoe County during the summer of 2015 that closed I-65 northbound.

The Lesser Known Side Of Highway Safety, Rick Drumm

Purdue Road School

Most highway professionals are aware of the main concepts of highway safety. But there are many other concepts, odd statistics, and unique countermeasures that are not well publicized and that we might consider brilliant—or silly. As a host of ideas are presented, you will be challenged to consider how to improve highway safety on your roads, and maybe share some of your own ideas.