Ola L A Harrysson

North Carolina State University | NCSU · Department of Industrial & Systems Engineering

A 2-year-old, male neutered, domestic short-hair cat presented with a 1-month history of non-specific pain, inappetence and paraparesis with a plantigrade gait. MR and CT imaging revealed a left-sided contrast-enhancing extradural mass at the T1-T2 intervertebral disc space, causing severe spinal cord compression. Materialise Mimics 3D medical imag...

This work expands the capabilities of the Digital Additive and Subtractive Hybrid (DASH) system by including "geometric qualification" of mechanical products. Specifically, this research incorporates the extended Additive Manufacturing Format files (AMF-TOL) which include American Society of Mechanical Engineers (ASME) Y14.5 specifications for plan...

This work expands the capabilities of the Digital Additive and Subtractive Hybrid (DASH) system by including "geometric qualification” of mechanical products. Specifically, this research incorporates the extended Additive Manufacturing Format files (AMF-TOL) which include American Society of Mechanical Engineers (ASME) Y14.5 specifications for plan...

Additive manufacturing (AM) of the nickel–titanium (NiTi) shape memory alloys (SMA) have provided novel component solutions with a variety of design configurations in the industry. Electron beam melting (EBM) is a trending metal additive manufacturing process for industrial applications in the field of biomedical and aerospace engineering. In this...

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Objective: To evaluate accuracy of articular surfaces determined by use of 2 perpendicular CT orientations, micro-CT, and laser scanning. Sample: 23 cat cadavers. Procedures: Images of antebrachia were obtained by use of CT (voxel size, 0.6 mm) in longitudinal orientation (CTLO images) and transverse orientation (CTTO images) and by use of mic...

Hybrid Manufacturing Processes (HMP) can significantly reduce time to customer, waste, and tooling costs per part, while increasing possible part geometric complexity for small batch parts. In the following chapter, HMP is defined by the production of parts produced first with a near-net shape process using methods including: additive manufacturing...

Objective This study assessed femur properties in 80 adult female rats exposed to a range of whole body vibration amplitudes at 45 Hz over five weeks. Our hypothesis was that an optimal amplitude for whole body vibration would be apparent and would result in increased bone strength. Methods Animals were treated in five amplitude groups (0 g, 0.15...

Additive manufacturing (AM) offers a fully integrated fabrication solution within many engineering applications. Particularly, it provides attractive processing alternatives for nickel-titanium (Ni–Ti) alloys to overcome traditional manufacturing challenges through layer by layer approach. Among powder-based additive manufacturing processes, the la...

Transcutaneous osseointegrated prostheses provide stable connections to the skeleton while eliminating skin lesions experienced with socket prosthetics. Additive manufacturing can create custom textured implants capable of interfacing with amputees' residual bones. Our objective was to compare osseointegration of textured surface implants made by e...

Additive manufacturing (AM) can significantly reduce the development time for small batch parts or parts with complicated geometries. However, the accuracy of most metal AM processes requires parts to be subjected to secondary processing (typically machining) in order to obtain requisite tolerances. Process plan development for hybrid manufacturing...

Two major problems are associated with total hip replacement: 1) stress shielding and 2) the adverse tissue reaction to certain elements of the implant material. In this regard, a porous implant provides lower stiffness and vacancies for bone ingrowth, making it more suitable for the human bone compared with a solid stem. Moreover, second-generatio...

In total hip arthroplasty (THA), the femoral stem can be fixed with or without bone cement. Cementless stem fixation is recommended for young and active patients as it eliminates the risk of loss of fixation at the bone-cement and cement-implant interfaces. Cementless fixation, however, suffers from a relatively high early revision rate. In the cur...

OBJECTIVE To assess 3-D geometry of the humerus of dogs and determine whether the craniocaudal canal flare index (CFI) is associated with specific geometric features. SAMPLE CT images (n = 40) and radiographs (38) for 2 groups of skeletally mature nonchondrodystrophic dogs. PROCEDURES General dimensions (length, CFI, cortical thickness, and humeral...

This work addresses a critical issue affecting the adoption of metal additive manufacturing (AM) methodologies; creating a system that can produce a mechanical product to final geometric specification. To date, almost all functional metal AM parts have required secondary processing that in many cases can more than double the cost of the final part....

OBJECTIVE To assess the repeatability and accuracy of polymer replicas of small, medium, and large long bones of small animals fabricated by use of 2 low-end and 2 high-end 3-D printers. SAMPLE Polymer replicas of a cat femur, dog radius, and dog tibia were fabricated in triplicate by use of each of four 3-D printing methods. PROCEDURES 3-D renderi...

Ti6Al4V porous scaffolds of two unit cell geometries (reentrant and cubic) were investigated as candidates for load-bearing biomedical applications. Samples were fabricated using an Arcam A2 electron beam melting (EBM) machine and evaluated for geometric deviation from the original CAD design using a digital optical microscope. The mass and boundin...

Osseointegrated implants transfer loads from native bone to a synthetic joint and can also function transdermally to provide a stable connection between the skeleton and the prostheses, eliminating many problems associated with socket prostheses. Additive manufacturing provides a cost-effective means to create patient-specific implants and allows f...

The objective of this work was to understand glucose oxidase (GOx) immobilization on mesoporous carbon (MC) and the electrochemical performance of a bio-anode fabricated from GOx-immobilized MC. GOx, MC, and NaCl concentrations significantly influenced GOx immobilization. The GOx enzyme adsorption on MC increased by 2.3 times when the total solute...

In additive manufacturing, microstructural control is feasible via processing parameter alteration. However, the window for parameter variation for certain materials, such as Ti-6Al-4V, is limited, and alternative methods must be employed to customize microstructures. Grain refinement and homogenization in cast titanium alloys has been demonstrated...

Aim of this study was to prove the possibility of manufacturing patient specific root analogue two-part (implant and abutment) implants by direct metal laser sintering. The two-part implant design enables covered healing of the implant. Therefore, CT-scans of three patients are used for reverse engineering of the implants, abutments and crowns. Pat...

Metal powder bed additive manufacturing technologies, such as the Electron Beam Melting process, facilitate a high degree of geometric flexibility and have been demonstrated as useful production techniques for metallic parts. However, the EBM process is typically associated with lower resolutions and higher surface roughness compared to similar la...

The present work was conducted as part of a larger America Makes funded project to begin to examine the effects of changes in process variables on the resulting microstructure and fracture and fatigue behavior of as-deposited Ti-6Al-4V. In addition to presenting initial results on process mapping of the electron beam powder bed process, the present...

Objective: To assess the geometry of canine humeri as seen on radiographs in chondrodystrophic dogs (CD) and brachycephalic dogs (BD) compared to non-chondrodystrophic dogs (NCD). Methods: Mediolateral (ML) and craniocaudal (CC) radiographs of skeletally mature humeri were used (CD [n = 5], BD [n = 9], NCD [n = 48]) to evaluate general dimension...

This overview highlights some of the key aspects regarding materials qualification needs across the AM spectrum. AM technology has experienced considerable publicity and growth in the past few years with many successful insertions for non-mission-critical applications. However, to meet the full potential that AM has to offer, especially for flight-...

This article presents economic models for a new hybrid method where additive manufacturing (AM) and subtractive methods (SMs) are integrated through composite process planning. Although AM and SM offer several unique advantages, there are technological limitations such as tolerance and surface finish requirements; tooling and fixturing, etc. that c...

While the tensile/compressive mechanical properties of the re-entrant auxetic cellular structure have been relatively well modeled, their shear properties including the shear modulus and shear strength have not been investigated. This paper focuses on the analytical modeling of the shear properties of this auxetic structure utilizing beam analysis....

div class="title">Novel Materials and Structures Fabricated by Electron Beam Melting - Volume 21 Issue S3 - Harvey West, Ola Harrysson, Tim Horn, Denis Cormier, Ron Aman, Denis Marcellin-Little

Purpose – The aim of this study is to perform a comparative study on sandwich structures with several types of three-dimensional (3D) reticulate cellular structural core designs for their low-energy impact absorption abilities using powder bed additive manufacturing methods. 3D reticulate cellular structures possess promising potentials in various...

This paper presents an integrated hybrid manufacturing approach to enhance and accelerate the adoption of metal Additive Manufacturing (AM) by adding a direct digital subtractive process to the production that is capable of improving the form, location and position tolerance of critical part features as well as improving surface finish. The hybrid...

Due to the rough nature of surfaces produced by current additive metal processes, a deviation between the nominal and actual pose of the part arises when fixturing in an NC machine. Modern 3D scanning systems are capable of generating high density measurements that may be used to localize the part and compensate for these errors; but require that s...

Objectives: As the process of additive manufacturing, or three-dimensional (3D) printing, has become more practical and affordable, a number of applications for the technology in the field of pediatric otolaryngology have been considered. One area of promise is temporal bone surgical simulation. Having previously developed a model for temporal bon...

This preliminary work documents the effects of test orientation with respect to build and beam raster directions on the fracture toughness and fatigue crack growth behavior of as-deposited EBM Ti-6Al-4V. Although ASTM standards exist for determining the orientation dependence of various mechanical properties in both cast and wrought materials, thes...

Direct metal fabrication systems like electron beam melting (EBM) and direct metal laser sintering (also called selective laser melting) are gaining popularity. One reason is the design and fabrication freedom that these technologies offer over traditional processes. One specific feature that is of interest is mesh or lattice structures that can be...

With the rapid development of additive manufacturing (AM), high-quality fabrication of lightweight design-efficient structures no longer poses an insurmountable challenge. On the other hand, much of the current research and development with AM technologies still focuses on material and process development. With the design for additive manufacturing...

Veterinary medicine has undergone a rapid increase in specialization over the last three decades. Veterinarians now routinely perform joint replacement, neurosurgery, limb-sparing surgery, interventional radiology, radiation therapy, and other complex medical procedures. Many procedures involve advanced imaging and surgical planning. Evidence-based...

A simulated, multicolor, multi-material temporal bone model can be created using 3-dimensional (3D) printing that will prove both safe and beneficial in training for actual temporal bone surgical cases. As the process of additive manufacturing, or 3D printing, has become more practical and affordable, a number of applications for the technology in...

The Regenerative Medicine Foundation Annual Conference held on May 6 and 7, 2014, had a vision of assisting with translating tissue engineering and regenerative medicine (TERM)-based technologies closer to the clinic. This vision was achieved by assembling leaders in the field to cover critical areas. Some of these critical areas included regulator...

Transdermal osseointegrated prostheses (TOPs) are emerging as an alternative to socket prostheses. Electron beam melting (EBM) is a promising additive manufacturing technology for manufacture of custom, freeform titanium alloy (Ti6Al4V) implants. Skin ongrowth for infection resistance and mechanical stability are critically important to the success...

Fully dense copper components with complex geometries were demonstrated. Two high-purity 99.99% Cu powders were atomized in argon; while a third low-purity 99.8% Cu powder (C) was atomized in air. Apparent density and volumetric flow rate of the three high-purity copper powder types were analyzed according to ASTM standards B703-10 and B855-06, res...

In direct metal additive manufacturing (AM), the ability to predict and control as-deposited microstructure can reduce post-processing and speed qualification. In this work, modeling and experimental results are presented for Ti64 prior beta grain size and morphology for two direct metal AM processes: Electron Beam Melting (EBM) by Arcam and Electr...

This talk gives an overview of an on-going project supported by America Makes (the National Additive Manufacturing Innovation Institute) that directly targets missing links for understanding and controlling microstructure and mechanical properties across both laser powder bed (EOS) and electron beam powder bed (Arcam) processes. Establishing these...

ABSTRACT As additive manufacturing, or 3D printing, has become more practical and affordable, a number of applications for the technology in the field of Otolaryngology-Head & Neck Surgery, and for pediatric otolaryngology in particular, have been considered. One area of promise may be in temporal bone surgical simulation. In this project, 3D model...

Purpose – The aim of this study is to describe an improved experimental substrate for the mechanical testing of patient-specific implants fabricated using direct metal additive manufacturing processes. This method reduces variability and sample size requirements and addresses the importance of geometry at the bone/implant interface. Design/methodo...

To describe clinical, radiographic, and computed tomographic (CT) assessment of biapical deformities of the radius in dogs and evaluate the effectiveness of their management by use of bilevel hinged circular external fixation frames. Prospective, non-randomized cohort study. Dogs (N = 26: 13 with 14 limbs operated, 13 controls). CT scans of the for...

Piriformis syndrome is an uncommon diagnosis for a non-discogenic form of sciatica whose treatment has traditionally focused on stretching the piriformis muscle (PiM). Conventional stretches include hip flexion, adduction, and external rotation. Using three-dimensional modeling, we quantified the amount of (PiM) elongation resulting from two conven...

Skin is a multilayered composite material and composed principally of the proteins collagen, elastic fibers, and fibroblasts. The direction-dependent material properties of skin tissue is important for physiological functions like skin expansion. The current study has developed methods to characterize the directional biomechanical properties of por...

In this study, the behavior of a parametric 3D re-entrant dodecahedron lattice structure with negative Poisson's ratio was studied. Four geometrical configurations for the re-entrant dodecahedron were designed, and the relationship between the mechanical properties and the design parameters was determined through beam theory. Samples were fabricate...

In this study, various sandwich panel structures with different reticulate lattice core geometries were designed and then fabricated in titanium via the electron beam melting (EBM) process. Bending tests were performed on the titanium samples, and mechanical properties such as modulus, bending strength, and energy absorption were evaluated. Differe...

Based on an analytical modeling analysis, a sandwich structure with a 3D re-entrant auxetic core was designed. Auxetic samples were produced by electron beam melting (EBM) and selective laser sintering (SLS), and compared to other regular cellular sandwich structures through various experiments. It was shown that sandwich structures with pre-design...

This paper details the design, fabrication, and testing of non-stochastic auxetic lattice lattice structures. All Ti–6Al–4V samples were created via the Electron Beam Melting (EBM) additive manufacturing process. It was found that the Poisson's ratio values significantly influence the mechanical properties of the structures. The bending properties...

Three-dimensional printing or rapid prototyping are processes by which components are fabricated directly from computer models by selectively curing, depositing or consolidating materials in successive layers. These technologies have traditionally been limited to the fabrication of models suitable for product visualization but, over the past decade...

In this current work, a Ti–6Al–4V 3-D re-entrant lattice auxetic structure is manufactured by the electron beam melting (EBM) process. Four different design configurations (two negative Poisson’s ratio values × two relative densities) were manufactured and tested under compressive stress. Two failure modes were observed whose occurrence appeared to...

Periodic lattice structures are three-dimensional arrays of unit cells having carefully engineered geometric properties. Solid Freeform Fabrication (SFF) processes have made it possible to tailor structural, thermal, or electrical properties by varying the shape and density of the unit-cell geometry. In this paper, the electrical conductivity of a...

To design and fabricate fiberglass-reinforced composite (FRC) replicas of a canine radius and compare their mechanical properties with those of radii from dog cadavers. Replicas based on 3 FRC formulations with 33%, 50%, or 60% short-length discontinuous fiberglass by weight (7 replicas/group) and 5 radii from large (> 30-kg) dog cadavers. Bones an...

To assess the effect of computed tomography (CT) scan protocols (radiation amounts) and fabrication methods on biomodel accuracy and variability. Cadaveric femur of a Basset Hound. Retroreconstructions (n = 158) were performed of 16 original scans and were visually inspected to select 17 scans to be used for biomodel fabrication. Biomodels of the 1...

Bone machining is a common procedure in a majority of orthopaedic surgeries. Machining parameters including spindle speed, feed rate, type of power system (pneumatic and electric) and tool design significantly influence the surface properties of the bone. Surface characteristics such as roughness (average and roughness gradient) and thermal damage...

Surgical power tools are comprised of electric and pneumatic systems. The main advantages of pneumatic systems regard safety and cost considerations. Typical surgical requirements encompass spinal, cranial, ENT and orthopedic procedures. Machining capabilities include drilling, broaching, sawing, reaming and milling. Adverse artifacts may be introd...

An orthotropic 3D re-entrant honeycomb structure that exhibits a negative Poisson's ratio was designed and fabricated via the electron beam melting (EBM) process. The modeling work established the relationships between various structural parameters and the mechanical properties of the auxetic structures. Compressive tests were performed on the re-e...

Auxetic structures have attracted a great deal of researcher due to their superior properties for use in various applications. Up until this point, most research regarding auxetic structures has been limited to theoretical analysis due to the difficulty of actually fabricating auxetic structures. In the current study, a periodic 3D orthotropic re-e...

In recent years, there has been a paradigm shift in the application of Additive Manufacturing (AM) processes as a low volume production system. Improved capabilities of several metal-based processes have made AM, a viable method to produce complex biomedical and aerospace parts. Often, such high performance parts are made of expensive alloys and th...

To design and manufacture free-form biodegradable polycaprolactone (PCL) bone plates and to compare mechanical properties of femoral constructs with a distal physeal fracture repaired by use of 5 stabilization methods. 40 canine femoral replicas created by use of additive manufacturing and rapid tooling. Surgery duration, mediolateral and craniocau...

Objective To compare an electron beam melting processed (EBMP) low-modulus titanium alloy mesh stem with a commercial cobalt-chromium (CC) stem in a canine cadaver model. Sample Population-9 pairs of cadaver femora. Procedures EBMP stems of 3 sizes were placed in randomly chosen sides of femora (left or right) and CC stems in opposite sides. Stem i...

To compare an electron beam melting-processed (EBMP) low-modulus titanium alloy mesh stem with a commercial cobalt-chromium (CC) stem in a canine cadaver model. 9 pairs of cadaver femora. EBMP stems of 3 sizes were placed in randomly chosen sides of femora (left or right) and CC stems in opposite sides. Stem impaction distances were recorded. Five...

Custom orthopedic implants may be generated using free-form fabrication methods (FFF) such as electron beam melting (EBM). EBM FFF may be used to make solid metal implants whose surface is often polished using CNC machining and porous scaffolds that are usually left unpolished. We assessed the in vitro biocompatibility of EBM titanium-6 aluminum-4...

A key issue for high average power, normal conducting radio frequency (NCRF), photoinjectors is efficient structure cooling. To that end, RadiaBeam has been developing the use of Solid Freeform Fabrication (SFF) for the production of NCRF photoinjectors. In this paper we describe the preliminary design, developed in collaboration with JLab, of a hi...

The performance of orthopedic implants is often evaluated using cadaveric bone specimens. The high inter-specimen variability of cadaveric bone properties requires large sample sizes to obtain statistical significance. With recent focus on custom implants manufactured using direct metal freeform fabrication techniques, the need for a customized bon...

Titanium lattice block structures fabricated via Electron Beam Melting (EBM) have received considerable interest in recent years. Lattice block structures have significant potential to reduce the weight of aerospace structures with minimal reduction of mechanical properties. However, the design and fabrication of titanium lattice block structures i...

Several direct metal fabrication technologies are available on the market for production of medical implants. Each technology has advantages and drawbacks and there is no consensus what constitutes optimal technology. These technologies are often considered to be competitors but that may not always be the case. Laser-based systems tend to be more a...

This paper addresses foams which are known as non-stochastic foams, lattice structures, or repeating open cell structure foams. The paper reports on preliminary research involving the design and fabrication of non-stochastic Ti–6Al–4V alloy structures using the electron beam melting (EBM) process. Non-stochastic structures of different cell sizes a...

To design and manufacture custom titanium bone plates and a custom cutting and drill guide by use of free-form fabrication methods and to compare variables and mechanical properties of 2 canine tibial plateau leveling methods with each other and with historical control values. 10 canine tibial replicas created by rapid prototyping methods. Applicat...

The design of custom or tailored implant components has been the subject of research and development for decades. However, the economic feasibility of fabricating such components has proven to be a challenge. New direct metal fabrication technologies such as Electron Beam Melting (EBM) have opened up new possibilities. This paper discusses the desi...

Purpose Optimization techniques can be used to design geometrically complex components with a wide variety of optimization criteria. However, such components have been very difficult and costly to produce. Layered fabrication technologies such as electron beam melting (EBM) open up new possibilities though. This paper seeks to investigate the integ...

Titanium aluminide (TiAl) is an intermetallic compound possessing excellent high-temperature performance while having significantly lower density than nickel-based superalloys. This paper presents preliminary results of experiments aimed at processing TiAl via the electron beam melting (EBM) process. Two processing routes are explored. The first us...

To report surgical planning, technique, and outcome of custom total knee replacement (TKR) performed to manage a medial femoral condylar nonunion in a dog. Clinical case report. A 3-year-old, 20 kg Karelian Bear Hound. Computed tomographic scan of the left pelvic limb was used to build a stereolithography model of the distal portion of the femur. T...