Polymeric composites exhibit time-dependent behavior, which raises a concern
about their long term durability and leads to a viscoelastic study of these materials.
Linear viscoelastic analysis has been found to be inadequate because many polymers
exhibit nonlinear viscoelastic behavior. Classical laminate theory is commonly used in
the study of laminated...
Ever since composite laminate technology was introduced into the aerospace and automotive industry, there has been a need to fully understand the damage progression experienced by composite laminated plates in the presence of a notch. While numerous research studies have been conducted on this matter when subjected to in-plane loads,...
This report is one of a series issued in cooperation with the Air Force-Navy-Civil Subcommittee on aircraft design criteria under the supervision of the Aircraft Committee of the Munitions Board. Information reviewed and reaffirmed 1959. Original report issued June 1953.
Revised April 1943. Publication restriction has been removed. This report is one of a series issued in cooperation with the Army Air Forces and the Bureau of Aeronautics under the supervision of the Aeronautical Board.
This report is one of a series issued in cooperation with the ANC-17 Panel on Plastics for Aircraft of the Departments of the Air Force, Navy, and Commerce. Information reviewed and reaffirmed 1959. Original report issued May 1954.
This report is one of a series issued in cooperation with the ANC-17 Panel on Plastics for Aircraft of the Departments of the Air Force, Navy, and Commerce. Information reviewed and reaffirmed 1960. Original report issued November 1955.
This report is one of a series issued in cooperation with the ANC-17 Panel on Plastics for Flight Vehicles of the Departments of the Air Force, Navy, and Commerce.
This report is one of a series issued in cooperation with the Air Force-Navy-Civil Subcommittee on Aircraft Design Criteria under the supervision of the Aircraft Committee of the Munitions Board. Information reviewed and reaffirmed July 1961. Original report published in February 1951.
This report is one of a series issued in cooperation with the ANC-17 Panel on Plastics for Aircraft of the Departments of the Air Force, Navy, and Commerce.
This report is one of a series issued in cooperation with the ANC-17 Panel on Plastics for Aircraft of the Departments of the Air Force, Navy, and Commerce.
This report is one of a series issued in cooperation with the ANC-17 Panel on Plastics for Flight Vehicles of the Departments of the Air Force, Navy, and Commerce. Information reviewed and reaffirmed 1960. Original report issued September 1955.
This report is one of a series issued in cooperation with the Army-Navy-Civil Committee on Aircraft Design Criteria under the supervision of the Aeronautical Board.
This report is one of a series issued in cooperation with the ANC-17 Panel on Plastics for Aircraft of the Departments of the Air Force, Navy, and Commerce. Information reviewed and reaffirmed 1965. Original report issued June 1957.
This report is one of a series issued in cooperation with the Air Force-Navy-Civil Subcommittee on Aircraft Design Criteria under the supervision of the Aircraft Committee of the Munitions Board. Information reviewed and reaffirmed 1958. Original report issued March 1952.
This report is one of a series issued in cooperation with the Air Force-Navy-Civil Subcommittee on Aircraft Design Criteria under the supervision of the Aircraft Committee of the Munitions Board. Information reviewed and reaffirmed 1958.
This report is one of a series issued in cooperation with the Air Force-Navy-Civil Subcommittee on Aircraft Design Criteria under the supervision of the Aircraft Committee of the Munitions Board. Information reviewed and reaffirmed July 1955 and 1960.
This report is one of a series issued in cooperation with the Army Air Forces and the Bureau of Aeronautics under the supervision of the Aeronautical Board.
This report is one of a series issued in cooperation with the Army-Navy-Civil Committee on Aircraft Design Criteria under the supervision of the Aeronautical Board.
This report is one of a series issued in cooperation with the Air Force-Navy-Civil Subcommittee on Aircraft Design Criteria under the supervision of the Aircraft Committee of the Munitions Board. Information reviewed and reaffirmed March 1955 and 1960. Results here reported were obtained during 1950.
This report is one of a series issued in cooperation with the ANC-17 Panel on Plastics for Aircraft of the Departments of the Air Force, Navy, and Commerce.
This report is one of a series issued in cooperation with the ANC-17 Panel on Plastics for Aircraft of the Departments of the Air Force, Navy, and Commerce. Information reviewed and reaffirmed 1962. Original report issued June 1956.
This report is one of a series issued in cooperation with the ANC-17 Panel on Plastics for Flight Vehicles of the Departments of the Air Force, Navy, and Commerce.
This report is one of a series issued in cooperation with the ANC-23 Panel on Composite Construction for Flight Vehicles of the Departments of the Air Force, Navy, and Commerce
This report is one of a series issued in cooperation with the ANC-17 Panel on Plastics for Aircraft of the Departments of the Air Force, Navy, and Commerce. Information reviewed and reaffirmed 1962. Original report issued November 1956.
This report is one of a series issued in cooperation with the ANC-17 Panel on Plastics for Aircraft of the Departments of the Air Force, Navy, and Commerce. Information reviewed and reaffirmed 1960. Original report issued September 1955.
This report is one of a series issued in cooperation with the Air Force-Navy-Civil Subcommittee on Aircraft Design Criteria under the supervision of the Aircraft Committee of the Munitions Board.
Metal-organic frameworks (MOFs) represent an exciting, new class of porous materials. Their hybrid organic-inorganic structure opens up near infinite possibilities to tune and design their structure for specific properties and applications. A new generation of flexible MOFs, following a generation of stiff MOFs, has created additional design space and complexity....
Hydrogel polymers are a novel class of hydrophilic materials that have large application areas in both the industrial and medical fields. Carboxymethyl cellulose (CMC) has received attention as a hydrogel polymer. Methods to modify the mechanical properties of gels and films made from CMC are of interest in our lab...
Epoxy resin is a thermosetting resin that is commonly used as composite matrix. Epoxy composite materials are well utilized in industries, such as aerospace, due to their good mechanical properties. Nano-scale filler reinforced polymer composite materials have been intensively researched in recent decades. Cellulose nanocrystals (CNXLs) are a type of...
Dental resin composites are widely used in modern dentistry due to their aesthetic appearance. However, resin based restorations have inferior mechanical properties (fracture is the second reason for restorations replacement) in comparison to alloy based composites and their antimicrobial properties still remain poor, leading to secondary tooth decay development on...
CPM-M4 tool steel is a commonly used knife blade material due to its high strength and wear resistance. The goal of this thesis is to understand how heat treatment parameters affect blade performance and microstructure.Five heat treatments were applied to CPM-M4 steel by varying austenitizing and tempering temperatures. The microstructures...
This report is one of a series issued in cooperation with the Army-Navy-Civil Committee on aircraft design criteria under the supervision of the aeronautical board. Information reviewed and reaffirmed 1962. Original material published 1944.
For resin based dental restorative composites, one of the major challenges is to optimize the balance between mechanical and optical properties. Although fracture is the second leading cause of dental restorative failures, very limited mechanistic understanding exists on a microscopic level. In the present study, the fracture properties and mechanisms...
This report is one of a series issued in cooperation with the ANC-23 Panel on Sandwich Construction for Aircraft of the departments of the Air Force, Navy, and Commerce. Information reviewed and reaffirmed 1965. Original report issued March 1957.
The objective of this research project was to increase the density, strength, and stiffness of two low to medium-density diffuse-porous hardwood species. Wood used in this study was processed using a method of wood densification known as “Viscoelastic Thermal Compression” (VTC). The VTC process is a three phase treatment which...
Today nano scale materials are being used for wide range of applications. One promising topic in nano scale materials is using them for reinforcement of different polymeric materials to reach desirable stiffness properties. The stiffness of these materials is mostly found experimentally because the nanocomposite community lacks a decent analytical...
This study examined the relationship of interfacial shear strength (IFSS) and
bending strength (MOR) of several different wood-plastic composites (WPC's).
Plastics utilized were high-density polyethylene (HDPE) and polypropylene (PP).
Pine and oak were used as the wood species. Compatibilizers used included maleicanhydride
polyethylene (MAPE), polymeric methylene diphenyl diisocyanate (PMDI),
KymeneTM,...
Information reviewed and reaffirmed, 1962. Original report published in 1943. This report is one of a series issued in cooperation with the Army-Navy-Civil Committee on Aircraft Design Criteria under the supervision of the Aeronautical Board.
Polylactic acid (PLA), a renewable material, is used widely in a variety of commercial and specialty applications. However, certain limitations such as high temperature stability and brittleness limit its applicability. This problem is addressed by reinforcing PLA with a variety of materials but the process gives rise to different issues...
Information reviewed and reaffirmed, 1962. Original report dated June 1943. This report is one of a series issued in cooperation with the Army-Navy-Civil Committee on Aircraft Design Criteria under the supervision of the Aeronautical Board.
This report is one of a series issued to aid the nation's war program. Information reviewed and reaffirmed 1956 and 1962. Report first issued March 1942.
Identifying material characteristics of composites is important in designing any
structural system. The aerospace industry relies on these material properties not only to
design a functional aircraft, but also a safe and reliable one. Since carbon fiber
composites are relatively new materials, little is known about its characteristics under
certain...
This report is one of a series issued in cooperation with the Army-Navy-Civil Committee on Aircraft Design Criteria under the supervision of the Aeronautical Board.
Local material damage that occurs within cellular solids, such as polymer foams and trabecular bone, and precedes local fractures of the cell struts or walls is called micro-damage. The accumulation of micro-damage within cellular solids is often undesirable, although it is thought to be vital to the development and health...
The effects of incorporation of selected biocides on physical and mechanical properties of aspen strandboard were assessed using five copper-based preservatives or zinc borate at three retention levels. Tebuconazole or 4,5-dichloro-2-N-octyl-4-isothiazolin-3-one (DCOI) were added as co-biocides to selective copper-based treatments. Mold box tests showed that only panels treated with DCOI...
Wood plastic composites (WPCs) are composite materials made from thermoplastic polymers, wood flour, and a small amount of process- and property-enhancing additives; they are principally used in the automotive industry and as secondary building materials. Although the WPC market is expected to keep growing, it is still relatively small when...
Wood stiffness is one of the most important properties of lumber and veneer. We studied wood stiffness (modulus of elasticity, MOE), wood density, microfibril angle, and knots in a 25 year-old wind pollinated progeny test (50 families, ~ 373 trees) of coastal Douglas-fir to understand the potential for genetically improving...
To remain competitive, the forest products industry needs to look for new and innovative processes and technologies to not only reduce costs but also to recover more value through the entire seedling-to-customer forest products supply chain. It is well recognized that measuring wood properties of logs in real time during...
This report is one of a series issued in cooperation with the ANC-23 Panel on Composite Construction for Flight Vehicles of the Departments of the Air Force, Navy, and Commerce. Information reviewed and reaffirmed 1962. Original report issued January 1956.
This report is one of a series issued in cooperation with Air Force-Navy-Civil Subcommittee on Aircraft Design Criteria under the supervision of the Aircraft Committee of the Munitions Board. Information reviewed and reaffirmed 1958. Original dated December 1951.
This report is one of a series issued in cooperation with the Air Force-Navy-Civil Subcommittee on Aircraft Design Criteria under the supervision of the Aircraft Committee of the Munitions Board. Information reviewed and reaffirmed 1962.
The goal of this project is to contribute to the development of design values for cross-laminated timber (CLT) diaphragms in the seismic load-resisting system for buildings. Monotonic and cyclic tests to determine strength and stiffness characteristics of 2.44 m (8 ft) long shear connections with common self-tapping screws were performed....