{"id":72,"date":"2020-10-12T21:52:10","date_gmt":"2020-10-12T21:52:10","guid":{"rendered":"https:\/\/box2367.temp.domains\/~berfield\/\/?page_id=72"},"modified":"2020-10-13T09:06:59","modified_gmt":"2020-10-13T13:06:59","slug":"research","status":"publish","type":"page","link":"https:\/\/berfieldgroup.com\/?page_id=72","title":{"rendered":"Research"},"content":{"rendered":"\n<ul class=\"wp-block-list\"><li><a href=\"#AMMetal\" data-type=\"internal\" data-id=\"#AMMetal\">Additive Manufacturing of Metals<\/a><\/li><li><a href=\"#PiezoPolymer\" data-type=\"internal\" data-id=\"#PiezoPolymer\">Piezoelectric Polymer Printing<\/a><\/li><li><a href=\"#EnergyHavesting\" data-type=\"internal\" data-id=\"#EnergyHavesting\">Energy Harvesting<\/a><\/li><li><a href=\"#ThinFilm\" data-type=\"internal\" data-id=\"#ThinFilm\">Thin Film Mechanics<\/a><\/li><\/ul>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"AMMetal\"><span class=\"has-inline-color has-vivid-red-color\">Additive Manufacturing of Metals<\/span> <\/h2>\n\n\n\n<h3 class=\"wp-block-heading\">Residual Stress Effects on AM Part Properties<\/h3>\n\n\n\n<div class=\"wp-block-columns is-layout-flex wp-container-core-columns-is-layout-8f761849 wp-block-columns-is-layout-flex\">\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\" style=\"flex-basis:66.66%\">\n<figure class=\"wp-block-image size-large\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" width=\"1010\" height=\"589\" src=\"https:\/\/i0.wp.com\/box2367.temp.domains\/~berfield\/\/wp-content\/uploads\/2020\/10\/Contour-Method-NIST-1024x597.jpg?resize=1010%2C589&#038;ssl=1\" alt=\"\" class=\"wp-image-73\" srcset=\"https:\/\/i0.wp.com\/berfieldgroup.com\/wp-content\/uploads\/2020\/10\/Contour-Method-NIST.jpg?resize=1024%2C597&amp;ssl=1 1024w, https:\/\/i0.wp.com\/berfieldgroup.com\/wp-content\/uploads\/2020\/10\/Contour-Method-NIST.jpg?resize=300%2C175&amp;ssl=1 300w, https:\/\/i0.wp.com\/berfieldgroup.com\/wp-content\/uploads\/2020\/10\/Contour-Method-NIST.jpg?resize=768%2C448&amp;ssl=1 768w, https:\/\/i0.wp.com\/berfieldgroup.com\/wp-content\/uploads\/2020\/10\/Contour-Method-NIST.jpg?resize=600%2C350&amp;ssl=1 600w, https:\/\/i0.wp.com\/berfieldgroup.com\/wp-content\/uploads\/2020\/10\/Contour-Method-NIST.jpg?resize=150%2C87&amp;ssl=1 150w, https:\/\/i0.wp.com\/berfieldgroup.com\/wp-content\/uploads\/2020\/10\/Contour-Method-NIST.jpg?w=1321&amp;ssl=1 1321w\" sizes=\"auto, (max-width: 1010px) 100vw, 1010px\" \/><figcaption>Contour method technique for residual stress measurement.<\/figcaption><\/figure>\n<\/div>\n\n\n\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\" style=\"flex-basis:33.33%\">\n<p class=\"wp-block-paragraph\">Our group performs mechanical response-based residual stress measurements, as shown here via the contour method on additive manufactured Ti-6Al-4V fatigue specimens.<\/p>\n<\/div>\n<\/div>\n\n\n\n<h3 class=\"wp-block-heading\">Laser Shock Peening Surface Treatments<\/h3>\n\n\n\n<div class=\"wp-block-columns is-layout-flex wp-container-core-columns-is-layout-8f761849 wp-block-columns-is-layout-flex\">\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\">\n<figure class=\"wp-block-image size-large\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" width=\"1002\" height=\"777\" src=\"https:\/\/i0.wp.com\/box2367.temp.domains\/~berfield\/\/wp-content\/uploads\/2020\/10\/LSPsampleJ.jpg?resize=1002%2C777&#038;ssl=1\" alt=\"\" class=\"wp-image-79\" srcset=\"https:\/\/i0.wp.com\/berfieldgroup.com\/wp-content\/uploads\/2020\/10\/LSPsampleJ.jpg?w=1002&amp;ssl=1 1002w, https:\/\/i0.wp.com\/berfieldgroup.com\/wp-content\/uploads\/2020\/10\/LSPsampleJ.jpg?resize=300%2C233&amp;ssl=1 300w, https:\/\/i0.wp.com\/berfieldgroup.com\/wp-content\/uploads\/2020\/10\/LSPsampleJ.jpg?resize=768%2C596&amp;ssl=1 768w, https:\/\/i0.wp.com\/berfieldgroup.com\/wp-content\/uploads\/2020\/10\/LSPsampleJ.jpg?resize=451%2C350&amp;ssl=1 451w, https:\/\/i0.wp.com\/berfieldgroup.com\/wp-content\/uploads\/2020\/10\/LSPsampleJ.jpg?resize=150%2C116&amp;ssl=1 150w\" sizes=\"auto, (max-width: 1002px) 100vw, 1002px\" \/><figcaption>LSP treated AM Ti-6Al-4V <\/figcaption><\/figure>\n<\/div>\n\n\n\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\">\n<figure class=\"wp-block-image size-large\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" width=\"1002\" height=\"777\" src=\"https:\/\/i0.wp.com\/box2367.temp.domains\/~berfield\/\/wp-content\/uploads\/2020\/10\/YAGLaser.jpg?resize=1002%2C777&#038;ssl=1\" alt=\"\" class=\"wp-image-78\" srcset=\"https:\/\/i0.wp.com\/berfieldgroup.com\/wp-content\/uploads\/2020\/10\/YAGLaser.jpg?w=1002&amp;ssl=1 1002w, https:\/\/i0.wp.com\/berfieldgroup.com\/wp-content\/uploads\/2020\/10\/YAGLaser.jpg?resize=300%2C233&amp;ssl=1 300w, https:\/\/i0.wp.com\/berfieldgroup.com\/wp-content\/uploads\/2020\/10\/YAGLaser.jpg?resize=768%2C596&amp;ssl=1 768w, https:\/\/i0.wp.com\/berfieldgroup.com\/wp-content\/uploads\/2020\/10\/YAGLaser.jpg?resize=451%2C350&amp;ssl=1 451w, https:\/\/i0.wp.com\/berfieldgroup.com\/wp-content\/uploads\/2020\/10\/YAGLaser.jpg?resize=150%2C116&amp;ssl=1 150w\" sizes=\"auto, (max-width: 1002px) 100vw, 1002px\" \/><figcaption>Variable fluence 200 mJ YAG laser<\/figcaption><\/figure>\n<\/div>\n\n\n\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\">\n<p class=\"wp-block-paragraph\">Application of nano-second YAG laser pulses under confinement induces a compressive surface stress state, improving fatigue performance.<\/p>\n<\/div>\n<\/div>\n\n\n\n<h3 class=\"wp-block-heading\">Lattice Structure Response<\/h3>\n\n\n\n<div class=\"wp-block-columns is-layout-flex wp-container-core-columns-is-layout-8f761849 wp-block-columns-is-layout-flex\">\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\">\n<figure class=\"wp-block-image size-large\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" width=\"984\" height=\"1024\" src=\"https:\/\/i0.wp.com\/berfieldgroup.com\/wp-content\/uploads\/2020\/10\/Cube_Samples-1.jpg?resize=984%2C1024&#038;ssl=1\" alt=\"\" class=\"wp-image-108\" srcset=\"https:\/\/i0.wp.com\/berfieldgroup.com\/wp-content\/uploads\/2020\/10\/Cube_Samples-1.jpg?resize=984%2C1024&amp;ssl=1 984w, https:\/\/i0.wp.com\/berfieldgroup.com\/wp-content\/uploads\/2020\/10\/Cube_Samples-1.jpg?resize=288%2C300&amp;ssl=1 288w, https:\/\/i0.wp.com\/berfieldgroup.com\/wp-content\/uploads\/2020\/10\/Cube_Samples-1.jpg?resize=768%2C800&amp;ssl=1 768w, https:\/\/i0.wp.com\/berfieldgroup.com\/wp-content\/uploads\/2020\/10\/Cube_Samples-1.jpg?resize=1475%2C1536&amp;ssl=1 1475w, https:\/\/i0.wp.com\/berfieldgroup.com\/wp-content\/uploads\/2020\/10\/Cube_Samples-1.jpg?resize=336%2C350&amp;ssl=1 336w, https:\/\/i0.wp.com\/berfieldgroup.com\/wp-content\/uploads\/2020\/10\/Cube_Samples-1.jpg?resize=144%2C150&amp;ssl=1 144w, https:\/\/i0.wp.com\/berfieldgroup.com\/wp-content\/uploads\/2020\/10\/Cube_Samples-1.jpg?w=1777&amp;ssl=1 1777w\" sizes=\"auto, (max-width: 984px) 100vw, 984px\" \/><figcaption>Face center cubic lattic unit cells suffering from progressive strut failure under tensile loading.<\/figcaption><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\"><\/p>\n<\/div>\n\n\n\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\">\n<p class=\"wp-block-paragraph\">Lattice structures enabled by AM allow for lightweight components. However, lattice structure failure modes often differ from bulk specimen behavior due to pronounced surface roughness and porosity infuences.<\/p>\n<\/div>\n\n\n\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\">\n<figure class=\"wp-block-image size-large\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" width=\"982\" height=\"1024\" src=\"https:\/\/i0.wp.com\/berfieldgroup.com\/wp-content\/uploads\/2020\/10\/creep-latticeBIG.jpg?resize=982%2C1024&#038;ssl=1\" alt=\"\" class=\"wp-image-107\" srcset=\"https:\/\/i0.wp.com\/berfieldgroup.com\/wp-content\/uploads\/2020\/10\/creep-latticeBIG.jpg?resize=982%2C1024&amp;ssl=1 982w, https:\/\/i0.wp.com\/berfieldgroup.com\/wp-content\/uploads\/2020\/10\/creep-latticeBIG.jpg?resize=288%2C300&amp;ssl=1 288w, https:\/\/i0.wp.com\/berfieldgroup.com\/wp-content\/uploads\/2020\/10\/creep-latticeBIG.jpg?resize=768%2C801&amp;ssl=1 768w, https:\/\/i0.wp.com\/berfieldgroup.com\/wp-content\/uploads\/2020\/10\/creep-latticeBIG.jpg?resize=1473%2C1536&amp;ssl=1 1473w, https:\/\/i0.wp.com\/berfieldgroup.com\/wp-content\/uploads\/2020\/10\/creep-latticeBIG.jpg?resize=336%2C350&amp;ssl=1 336w, https:\/\/i0.wp.com\/berfieldgroup.com\/wp-content\/uploads\/2020\/10\/creep-latticeBIG.jpg?resize=144%2C150&amp;ssl=1 144w, https:\/\/i0.wp.com\/berfieldgroup.com\/wp-content\/uploads\/2020\/10\/creep-latticeBIG.jpg?w=1777&amp;ssl=1 1777w\" sizes=\"auto, (max-width: 982px) 100vw, 982px\" \/><figcaption>Single cell specimen for determining AM IN625 lattice structure creep response.<\/figcaption><\/figure>\n<\/div>\n<\/div>\n\n\n\n<h3 class=\"wp-block-heading\">Anisotropic Thermal Response of AM Parts<\/h3>\n\n\n\n<div class=\"wp-block-columns is-layout-flex wp-container-core-columns-is-layout-8f761849 wp-block-columns-is-layout-flex\">\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\">\n<figure class=\"wp-block-image size-large\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" width=\"509\" height=\"661\" src=\"https:\/\/i0.wp.com\/berfieldgroup.com\/wp-content\/uploads\/2020\/10\/Web_ThermalDIC.jpg?resize=509%2C661&#038;ssl=1\" alt=\"\" class=\"wp-image-88\" srcset=\"https:\/\/i0.wp.com\/berfieldgroup.com\/wp-content\/uploads\/2020\/10\/Web_ThermalDIC.jpg?w=509&amp;ssl=1 509w, https:\/\/i0.wp.com\/berfieldgroup.com\/wp-content\/uploads\/2020\/10\/Web_ThermalDIC.jpg?resize=231%2C300&amp;ssl=1 231w, https:\/\/i0.wp.com\/berfieldgroup.com\/wp-content\/uploads\/2020\/10\/Web_ThermalDIC.jpg?resize=270%2C350&amp;ssl=1 270w, https:\/\/i0.wp.com\/berfieldgroup.com\/wp-content\/uploads\/2020\/10\/Web_ThermalDIC.jpg?resize=116%2C150&amp;ssl=1 116w\" sizes=\"auto, (max-width: 509px) 100vw, 509px\" \/><figcaption>Thermal strain measurements via 3D digital image correlation.<\/figcaption><\/figure>\n<\/div>\n\n\n\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\">\n<p class=\"wp-block-paragraph\">Due to the layered build process and laser scan strategy, AM components demonstrate an orienation dependency in their thermal expansion response. We have quantified these effects for multiple thermal cycles using digital image correlation. <\/p>\n\n\n\n<p class=\"wp-block-paragraph\">This information is important for accurate predictions of thermally-driven residual stress accumulation during deposition. Unchecked, these stresses can crack AM components before they are even finished being made.  <\/p>\n<\/div>\n<\/div>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"PiezoPolymer\"><span class=\"has-inline-color has-vivid-red-color\">Piezoelectric Polymer Printing<\/span><\/h2>\n\n\n\n<h3 class=\"wp-block-heading\">Polyvinylidene Fluoride (PVDF) Feedstock<\/h3>\n\n\n\n<div class=\"wp-block-columns is-layout-flex wp-container-core-columns-is-layout-8f761849 wp-block-columns-is-layout-flex\">\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\">\n<p class=\"wp-block-paragraph\">Material extrusion additive manufacturing (MEAM) of the piezoelectric polymer PVDF is quite challenging due to the high coefficient of thermal expansion and difficulting in controlling microstructure. Our group has refined printing parameters and explored in situ electrical fields as means for enhancing PVDF printability and properties.<\/p>\n<\/div>\n\n\n\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\">\n<figure class=\"wp-block-image size-full\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" width=\"668\" height=\"376\" src=\"https:\/\/i0.wp.com\/berfieldgroup.com\/wp-content\/uploads\/2020\/10\/PVDF_Stock.png?resize=668%2C376&#038;ssl=1\" alt=\"\" class=\"wp-image-92\" srcset=\"https:\/\/i0.wp.com\/berfieldgroup.com\/wp-content\/uploads\/2020\/10\/PVDF_Stock.png?w=668&amp;ssl=1 668w, https:\/\/i0.wp.com\/berfieldgroup.com\/wp-content\/uploads\/2020\/10\/PVDF_Stock.png?resize=300%2C169&amp;ssl=1 300w, https:\/\/i0.wp.com\/berfieldgroup.com\/wp-content\/uploads\/2020\/10\/PVDF_Stock.png?resize=622%2C350&amp;ssl=1 622w, https:\/\/i0.wp.com\/berfieldgroup.com\/wp-content\/uploads\/2020\/10\/PVDF_Stock.png?resize=150%2C84&amp;ssl=1 150w\" sizes=\"auto, (max-width: 668px) 100vw, 668px\" \/><figcaption>PVDF material in raw pellet and extruded filament forms prior to MEAM deposition.<\/figcaption><\/figure>\n\n\n\n<figure class=\"wp-block-image size-large\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" width=\"588\" height=\"238\" src=\"https:\/\/i0.wp.com\/berfieldgroup.com\/wp-content\/uploads\/2020\/10\/SmallPVDFdogbone-copy.png?resize=588%2C238&#038;ssl=1\" alt=\"\" class=\"wp-image-96\" srcset=\"https:\/\/i0.wp.com\/berfieldgroup.com\/wp-content\/uploads\/2020\/10\/SmallPVDFdogbone-copy.png?w=588&amp;ssl=1 588w, https:\/\/i0.wp.com\/berfieldgroup.com\/wp-content\/uploads\/2020\/10\/SmallPVDFdogbone-copy.png?resize=300%2C121&amp;ssl=1 300w, https:\/\/i0.wp.com\/berfieldgroup.com\/wp-content\/uploads\/2020\/10\/SmallPVDFdogbone-copy.png?resize=150%2C61&amp;ssl=1 150w\" sizes=\"auto, (max-width: 588px) 100vw, 588px\" \/><figcaption>3D printd PVDF dogbone for mechanical testing. <\/figcaption><\/figure>\n<\/div>\n<\/div>\n\n\n\n<h3 class=\"wp-block-heading\">Piezoelectric Response of MEAM PVDF<\/h3>\n\n\n\n<div class=\"wp-block-columns is-layout-flex wp-container-core-columns-is-layout-8f761849 wp-block-columns-is-layout-flex\">\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\" style=\"flex-basis:33.33%\">\n<p class=\"wp-block-paragraph\">Optimizing PVDF deposition parameters and wiring with electrodes enables custom parts to be printed with piezoelectric sensing or actuation capabilities for &#8220;smart structure&#8221; applications. <\/p>\n<\/div>\n\n\n\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\" style=\"flex-basis:66.66%\">\n<figure class=\"wp-block-video\"><video height=\"720\" style=\"aspect-ratio: 1280 \/ 720;\" width=\"1280\" controls src=\"https:\/\/berfieldgroup.com\/wp-content\/uploads\/2020\/10\/PVDF_Printed_Scope.mp4\"><\/video><figcaption>Voltage response of a 3D printed PVDF beam with bonded electrodes being &#8220;plucked&#8221; as an input load.<\/figcaption><\/figure>\n<\/div>\n<\/div>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"EnergyHavesting\"><span class=\"has-inline-color has-vivid-red-color\">Energy Harvesting<\/span><\/h2>\n\n\n\n<h3 class=\"wp-block-heading\">Dynamic Response of Buckled Structures<\/h3>\n\n\n\n<div class=\"wp-block-columns is-layout-flex wp-container-core-columns-is-layout-8f761849 wp-block-columns-is-layout-flex\">\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\" style=\"flex-basis:66.66%\">\n<figure class=\"wp-block-image size-large is-resized\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" src=\"https:\/\/i0.wp.com\/berfieldgroup.com\/wp-content\/uploads\/2020\/10\/TorsionArmBuckled.png?resize=365%2C205&#038;ssl=1\" alt=\"\" class=\"wp-image-100\" width=\"365\" height=\"205\" srcset=\"https:\/\/i0.wp.com\/berfieldgroup.com\/wp-content\/uploads\/2020\/10\/TorsionArmBuckled.png?w=936&amp;ssl=1 936w, https:\/\/i0.wp.com\/berfieldgroup.com\/wp-content\/uploads\/2020\/10\/TorsionArmBuckled.png?resize=300%2C169&amp;ssl=1 300w, https:\/\/i0.wp.com\/berfieldgroup.com\/wp-content\/uploads\/2020\/10\/TorsionArmBuckled.png?resize=768%2C433&amp;ssl=1 768w, https:\/\/i0.wp.com\/berfieldgroup.com\/wp-content\/uploads\/2020\/10\/TorsionArmBuckled.png?resize=620%2C350&amp;ssl=1 620w, https:\/\/i0.wp.com\/berfieldgroup.com\/wp-content\/uploads\/2020\/10\/TorsionArmBuckled.png?resize=150%2C85&amp;ssl=1 150w\" sizes=\"auto, (max-width: 365px) 100vw, 365px\" \/><figcaption>Torque-arm actuated buckled beam energy harvesting device schematic. <\/figcaption><\/figure>\n\n\n\n<figure class=\"wp-block-image size-large\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" width=\"827\" height=\"514\" src=\"https:\/\/i0.wp.com\/berfieldgroup.com\/wp-content\/uploads\/2020\/10\/FrequencyPlot.png?resize=827%2C514&#038;ssl=1\" alt=\"\" class=\"wp-image-101\" srcset=\"https:\/\/i0.wp.com\/berfieldgroup.com\/wp-content\/uploads\/2020\/10\/FrequencyPlot.png?w=827&amp;ssl=1 827w, https:\/\/i0.wp.com\/berfieldgroup.com\/wp-content\/uploads\/2020\/10\/FrequencyPlot.png?resize=300%2C186&amp;ssl=1 300w, https:\/\/i0.wp.com\/berfieldgroup.com\/wp-content\/uploads\/2020\/10\/FrequencyPlot.png?resize=768%2C477&amp;ssl=1 768w, https:\/\/i0.wp.com\/berfieldgroup.com\/wp-content\/uploads\/2020\/10\/FrequencyPlot.png?resize=563%2C350&amp;ssl=1 563w, https:\/\/i0.wp.com\/berfieldgroup.com\/wp-content\/uploads\/2020\/10\/FrequencyPlot.png?resize=150%2C93&amp;ssl=1 150w\" sizes=\"auto, (max-width: 827px) 100vw, 827px\" \/><figcaption>Operational frequency bandwidth versus buckled beam compressive stress state, showing regimes of buckled state switching behavior for torque-arm energy harvester.<\/figcaption><\/figure>\n<\/div>\n\n\n\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\" style=\"flex-basis:33.33%\">\n<p class=\"wp-block-paragraph\">Structures with multiple stable buckled states offer potential advantages for vibration-based energy harvesting devices. The nonlinear behavior of these buckled structures broadens the bandwidth of viable energy harvesting vibration frequencies and produces large strains\/energy production outputs associated with transitioning between buckled states.  <\/p>\n<\/div>\n<\/div>\n\n\n\n<h3 class=\"wp-block-heading\">MEMS-Scale Energy Harvesting<\/h3>\n\n\n\n<div class=\"wp-block-columns is-layout-flex wp-container-core-columns-is-layout-8f761849 wp-block-columns-is-layout-flex\">\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\">\n<p class=\"wp-block-paragraph\">By prescribing the power level duty cycle during plasma-enhanced chemical vapor deposition of silicon nitride, a tightly controlled compressive residual stress state can be engineered. These residual stresses can be used to make buckled MEMS devices with nonlinear dynamic behavior, offering larger deflections and lower natural frequencies than their linear behavior counterparts. <\/p>\n<\/div>\n\n\n\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\">\n<figure class=\"wp-block-image size-large\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" width=\"941\" height=\"675\" src=\"https:\/\/i0.wp.com\/berfieldgroup.com\/wp-content\/uploads\/2020\/10\/PrototypeBuckledMass-BeforeAfter-ReleaseRotate2.jpg?resize=941%2C675&#038;ssl=1\" alt=\"\" class=\"wp-image-103\" srcset=\"https:\/\/i0.wp.com\/berfieldgroup.com\/wp-content\/uploads\/2020\/10\/PrototypeBuckledMass-BeforeAfter-ReleaseRotate2.jpg?w=941&amp;ssl=1 941w, https:\/\/i0.wp.com\/berfieldgroup.com\/wp-content\/uploads\/2020\/10\/PrototypeBuckledMass-BeforeAfter-ReleaseRotate2.jpg?resize=300%2C215&amp;ssl=1 300w, https:\/\/i0.wp.com\/berfieldgroup.com\/wp-content\/uploads\/2020\/10\/PrototypeBuckledMass-BeforeAfter-ReleaseRotate2.jpg?resize=768%2C551&amp;ssl=1 768w, https:\/\/i0.wp.com\/berfieldgroup.com\/wp-content\/uploads\/2020\/10\/PrototypeBuckledMass-BeforeAfter-ReleaseRotate2.jpg?resize=488%2C350&amp;ssl=1 488w, https:\/\/i0.wp.com\/berfieldgroup.com\/wp-content\/uploads\/2020\/10\/PrototypeBuckledMass-BeforeAfter-ReleaseRotate2.jpg?resize=150%2C108&amp;ssl=1 150w\" sizes=\"auto, (max-width: 941px) 100vw, 941px\" \/><figcaption>MEMS-scale energy harvesting device from topside (left) and bottom (right).<\/figcaption><\/figure>\n\n\n\n<figure class=\"wp-block-image size-large\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" width=\"402\" height=\"282\" src=\"https:\/\/i0.wp.com\/berfieldgroup.com\/wp-content\/uploads\/2020\/10\/Buckled_MEMS-1.png?resize=402%2C282&#038;ssl=1\" alt=\"\" class=\"wp-image-111\" srcset=\"https:\/\/i0.wp.com\/berfieldgroup.com\/wp-content\/uploads\/2020\/10\/Buckled_MEMS-1.png?w=402&amp;ssl=1 402w, https:\/\/i0.wp.com\/berfieldgroup.com\/wp-content\/uploads\/2020\/10\/Buckled_MEMS-1.png?resize=300%2C210&amp;ssl=1 300w, https:\/\/i0.wp.com\/berfieldgroup.com\/wp-content\/uploads\/2020\/10\/Buckled_MEMS-1.png?resize=150%2C105&amp;ssl=1 150w\" sizes=\"auto, (max-width: 402px) 100vw, 402px\" \/><figcaption>Release buckled beam MEMS harvester.<\/figcaption><\/figure>\n<\/div>\n<\/div>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"ThinFilm\"><span class=\"has-inline-color has-vivid-red-color\">Thin Film Mechanics<\/span><\/h2>\n\n\n\n<h3 class=\"wp-block-heading\">Thin Film Cracking<\/h3>\n\n\n\n<div class=\"wp-block-columns is-layout-flex wp-container-core-columns-is-layout-8f761849 wp-block-columns-is-layout-flex\">\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\" style=\"flex-basis:66.66%\">\n<figure class=\"wp-block-image size-large\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" width=\"666\" height=\"606\" src=\"https:\/\/i0.wp.com\/berfieldgroup.com\/wp-content\/uploads\/2020\/10\/WebCracksThinFilm.jpg?resize=666%2C606&#038;ssl=1\" alt=\"\" class=\"wp-image-113\" srcset=\"https:\/\/i0.wp.com\/berfieldgroup.com\/wp-content\/uploads\/2020\/10\/WebCracksThinFilm.jpg?w=666&amp;ssl=1 666w, https:\/\/i0.wp.com\/berfieldgroup.com\/wp-content\/uploads\/2020\/10\/WebCracksThinFilm.jpg?resize=300%2C273&amp;ssl=1 300w, https:\/\/i0.wp.com\/berfieldgroup.com\/wp-content\/uploads\/2020\/10\/WebCracksThinFilm.jpg?resize=385%2C350&amp;ssl=1 385w, https:\/\/i0.wp.com\/berfieldgroup.com\/wp-content\/uploads\/2020\/10\/WebCracksThinFilm.jpg?resize=150%2C136&amp;ssl=1 150w\" sizes=\"auto, (max-width: 666px) 100vw, 666px\" \/><figcaption>PZT sol-gel film deposited on an ODTS functionalized Si\/SiO2 substrate show widespread periodic cracking under mild heat treatment (~100 deg. C).<\/figcaption><\/figure>\n<\/div>\n\n\n\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\" style=\"flex-basis:33.33%\">\n<p class=\"wp-block-paragraph\">Extremely thin films (100s of nm in thickness) are susceptible to periodic cracking when drying, especially if deposited on a mediated film layer that prevents bonding. Such cracking, when controlled, can be used as a template for further film patterning, similar to conventional microfabrication techniques, though without the equipment.<\/p>\n<\/div>\n<\/div>\n\n\n\n<h3 class=\"wp-block-heading\">Laser Spallation Adhesion Measurements<\/h3>\n\n\n\n<div class=\"wp-block-columns is-layout-flex wp-container-core-columns-is-layout-8f761849 wp-block-columns-is-layout-flex\">\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\">\n<p class=\"wp-block-paragraph\">Laser spallation is a non-contact method for quantifying adhesion strength between a film and substrate. A nano-second laser pulse induces a rapidly expanding plasma to generate a shock wave that propogates through the specimen, ultimately loading the film-substrate interface in tension.<\/p>\n<\/div>\n\n\n\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\">\n<figure class=\"wp-block-image size-large\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" width=\"462\" height=\"232\" src=\"https:\/\/i0.wp.com\/berfieldgroup.com\/wp-content\/uploads\/2020\/10\/SpallSchem-1.png?resize=462%2C232&#038;ssl=1\" alt=\"\" class=\"wp-image-119\" srcset=\"https:\/\/i0.wp.com\/berfieldgroup.com\/wp-content\/uploads\/2020\/10\/SpallSchem-1.png?w=462&amp;ssl=1 462w, https:\/\/i0.wp.com\/berfieldgroup.com\/wp-content\/uploads\/2020\/10\/SpallSchem-1.png?resize=300%2C151&amp;ssl=1 300w, https:\/\/i0.wp.com\/berfieldgroup.com\/wp-content\/uploads\/2020\/10\/SpallSchem-1.png?resize=150%2C75&amp;ssl=1 150w\" sizes=\"auto, (max-width: 462px) 100vw, 462px\" \/><figcaption>Schematic of laser spallation test.<\/figcaption><\/figure>\n\n\n\n<figure class=\"wp-block-image size-large\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" width=\"294\" height=\"270\" src=\"https:\/\/i0.wp.com\/berfieldgroup.com\/wp-content\/uploads\/2020\/10\/FilmSpalled.png?resize=294%2C270&#038;ssl=1\" alt=\"\" class=\"wp-image-118\" srcset=\"https:\/\/i0.wp.com\/berfieldgroup.com\/wp-content\/uploads\/2020\/10\/FilmSpalled.png?w=294&amp;ssl=1 294w, https:\/\/i0.wp.com\/berfieldgroup.com\/wp-content\/uploads\/2020\/10\/FilmSpalled.png?resize=150%2C138&amp;ssl=1 150w\" sizes=\"auto, (max-width: 294px) 100vw, 294px\" \/><figcaption>Spalled film surface at high-laser fluence level.<\/figcaption><\/figure>\n<\/div>\n<\/div>\n","protected":false},"excerpt":{"rendered":"<p>Additive Manufacturing of Metals Piezoelectric Polymer Printing Energy Harvesting Thin Film Mechanics Additive Manufacturing of Metals Residual Stress Effects on AM Part Properties Our group performs mechanical response-based residual stress measurements, as shown here via the contour method on additive manufactured Ti-6Al-4V fatigue specimens. Laser Shock Peening Surface Treatments Application&#8230; <a class=\"continue-reading-link\" href=\"https:\/\/berfieldgroup.com\/?page_id=72\">Continue reading<\/a><\/p>\n","protected":false},"author":1,"featured_media":112,"parent":0,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"nf_dc_page":"","om_disable_all_campaigns":false,"_monsterinsights_skip_tracking":false,"footnotes":""},"class_list":["post-72","page","type-page","status-publish","has-post-thumbnail","hentry"],"jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/berfieldgroup.com\/index.php?rest_route=\/wp\/v2\/pages\/72","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/berfieldgroup.com\/index.php?rest_route=\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/berfieldgroup.com\/index.php?rest_route=\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/berfieldgroup.com\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/berfieldgroup.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=72"}],"version-history":[{"count":6,"href":"https:\/\/berfieldgroup.com\/index.php?rest_route=\/wp\/v2\/pages\/72\/revisions"}],"predecessor-version":[{"id":180,"href":"https:\/\/berfieldgroup.com\/index.php?rest_route=\/wp\/v2\/pages\/72\/revisions\/180"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/berfieldgroup.com\/index.php?rest_route=\/wp\/v2\/media\/112"}],"wp:attachment":[{"href":"https:\/\/berfieldgroup.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=72"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}