Sea Shells are natural-biological objects. They are embedded in geological layers in the form of fossils, but also, to find in archaeological deposits as a result of human activities. Archaeologists can use the provenance of Shells in the functional analysis of ancient sites in terms of social archeology and prehistoric trading activities. Aarcheological excavations in several sites of the Iranian Plateau have shown that from the 3rd third millennium B.C. onwards, finds of of sea Shells (e.g. Lambis, Dentalium, etc.) rapidely increased. Such Shells were for instance discovered from ritual cemetery contexts such as Shahdad, Tepe Hesar, Kale Nisar cemeteries or Bani Surma. These objects are mainly used as natural or polished Shells. In some cases, they served as a raw material for making all kinds of beads, buttons, and other ornamental objects.. The main question is to understand the relationship between the use of seaShells and archaeological context, and also, their role in Bronze Age ritual life. In this article, the descriptive, analytical method has been used in the biological recognition of all types of Shells. This method is also used based on similar studies on this issue in Mesopotamia's archeology of the Sumerian-Akkadian period. The distribution of recognizable species shows that these objects are concentrated in the settlements from south to southeast of Iran in the coastal strip of the Persian Gulf, and from the Oman Sea to the Zagros intermountain valleys, as well as in the northwest and northeast of Iran. The biological origin can be placed in the northern shores of the Oman Sea to the Gulf of Kutch on the northern coast of the Indian Ocean. It seems that with the growth and development of urbanization in Southwest Asia and especially the development of sea trade, oysters have been traded as valuable goods and other prestige goods. The importance of the Shell findings is more than the value of the Shells themselves because they were used as sacred goods in religious affairs. Analysis of the fields where the Shells were discovered is more related to cemeteries and temples as sacred spaces. Also, the significant presence of Lambis Shells for the production of specific ritual bowls, placed together with bronze axes in graves, can be seen as the reflection of a patriarchic tradition in the social-political organisiation of the third and second millennia B.C. Despite many excavations and the discovery of many samples of these types of Shells, no furthergoing investigation on these specific objects was undertaken so far. This desideratum reveals more valuable findings in the archeology of the Iranian plateau. Therefore, one of this article's final goals is to focus more on analyzing the context of the discovery of seaShells in future Excavation

Master Moulds are used to cast copper anode Moulds. These Moulds are made of grey or nodular castitons, because they posses the desired properties. It was expected that ductile cast iron Moulds could have performed their nominal life but in service; these Moulds have not performed their nominal life and they have experienced premature failures due to warping and cracking, Also grey cast iron Moulds fail because of generalized surface cracks. In this paper, the failure of master Moulds is investigated according to the metallographic and hardness measurement test. Then paralytic and austempered ductile iron alloys are proposed and tested through short time high temperature tensile and thermal shock test similar to working conditions of the Moulds. Also master Mould is modeled by Finite Element Method to evaluate the thermal conditions. Finally it is concluded that compared with paralytic ductile iron, austempered ductile iron has higher resistance to thermal shock.

In this investigation for Expandable Pattern Casting (EPC) simulation, an algorithm was developed to calculate the gas pressure of the evaporated foam during Mould filling. Also, the effect of backpressure evaporative foam on filling behavior was modeled with a new experimental function by adding a Volume of Fraction (VOF) function. The simulation of molten flow and track free surfaces is based on the (Solution Algorithm) SOLA-VOF numerical technique. To simulate the three-dimensional incompressible flow of melt in EPC Moulds, the pressure boundary conditions, heat transfer and foam gas pressure effect were modified. In order to verify the computational results of simulation melt flow in EPC casting, a thin grey iron plate was poured into a transparent foam Mould. Mould .filling and foam depolymerization were recorded with a 16mm high-speed camera. The comparison of experimental and simulation results of the sequence filling of EPC casting showed a good consistency, which confirms the accuracy of the model.

In this paper, the heat transfer coefficient on the A356 alloy metal-Mould interface for HI3 steel and Gray Iron Moulds was measured and modeled. Conditions as same as the low-pressure casting conditions were imposed by adding a piston, into the sprue channel. In order to establish one dimensional heat transfer condition, a cylindrical chalky sleeve was placed around of the Mould cavity, and then metallic chills (H13 and Gray Iron) are placed at the bottom and the top of the Mould cavity. Once purring, the time-temperature (T-t) curves at the interface of chill-Mould were saved and plotted by a data acquisition system. Then a mathematical model was introduced for the heat transfer coefficient of the metal Mould interface based on the experimental data by utilizing of "inverse heat problems" method. A simulation code of heat transfer was developed by finite difference method (FDM) that it could simulated distribution of heat transfer into at the mold and the cast part. The results of this code showed a sufficient agreement between the simulation and the experimental data.