The accumulation of synthetic debris in marine and coastal environments is a consequence of the intensive and continuous release of these highly persistent materials. This study investigates the current status of marine debris ingestion by sea turtles and seabirds found along the southern Brazilian coast. All green turtles (n=34) and 40% of the seabirds (14 of 35) were found to have ingested de...

Tool steels are a widely used material for construction of tools designated for shaping and forming of metal, plastic and other elements in mass production. These elements include extruding dies, pressure casting dies, moulds, punches and various other elements for plastic shaping of other materials preheated to temperatures in the range of 250-700 °C (Fig. 1). Since shape stability constitutes...

Management of municipal solid wastes (MSW) in most developed societies now involves the use of thermo-chemical conversion methods. This leads to energy and material recovery while also protecting the environment. However, till date most of the wastes generated in Nigeria (including plastic wastes) are either land-filled or openly burnt. These methods are not sustainable and environmentally non-...

The advanced transient concrete model (ATCM) is an extended model for concrete in compression at elevated temperature that incorporates elastic, plastic and creep strain as a function of temperature and stress history. The ATCM is applied with the material model of the thermal induced strain model. The non-linear model comprises thermal strain, elastic strain, plastic strain and transient tempe...

We study elasto-plastic deformations of unidirectional fiber reinforced polymeric composites (UFPCs) with fibers assumed to deform elastically and the matrix elasto-plastically. The matrix’s and hence composite’s plastic deformations are analyzed by using both the pressure-independent von Mises yield surface and the pressure-dependent Drucker–Prager yield surface and the associated flow rules. ...

In this paper, the study of efficient bonding characteristics of AA6014 and AA1050 metal strips is carried out for Accumulative Roll Bonding (ARB) process. Among various Severe Plastic Deformation (SPD) techniques, ARB process is widely used due to its ability to produce ultra-fine grained ( UFG) or nanostructured bulk material. It has been observed that, if the experimental pressure and corres...

We propose a mechanisms-based viscoplasticity approach for metals and alloys. First, we derive a stochastic model for thermally-activated motion of dislocations and, then, introduce power-law flow rules. The overall plastic deformation includes local plastic slip events taken with an appropriate weight assigned to each angle of the plane misorientation from the direction of maximum shear stress...

This paper presents the development and application of a 3D microstructure assembly process Plastic Deformation Magnetic Assembly (PDMA). In PDMA, certain part of a microstructure is plastically deformed by the magnetic force generated in a magnetic material piece attached to the microstructure when an external magnetic field is applied. Due to this plastic deformation, the entire microstructur...

A finite element model is developed to study the transient thermo-mechanical contact between a rigid sphere and an elastic–plastic sphere. Interference and tangential displacement are applied to the rigid sphere while the elastic–plastic sphere is stationary. The radius of the rigid sphere is larger than that of the elastic–plastic sphere to model flattening. Universal solutions are obtained fo...

The triaxiality of the stress state is known to greatly influence the amount of plastic strain which a material may undergo before ductile failure occurs. It is defined as the ratio of hydrostatic pressure, or mean stress, to the von Mises equivalent stress. This paper discusses the effects of stress triaxiality on yielding behavior of anisotropic materials. Hill-von Mises’s criteria for anisot...