The paper aims to outline the causes that affected a rare earth metal producer Molycorp Silmet's internationalization based on case study evidence. Moreover, based on statistical analysis, it aims to study how its internationalization and financial performance were interconnected. It concludes that 1) its export fluctuations mostly resulted from external factors and that despite such fluctuations, the firm's financial health was mostly good, 2) high concentration on a single target market can lower profitability, 3) fluctuations in target market shares can increase or decrease a firm's profitability, but they are not interconnected with its bankruptcy probability.
Electron backscatter diffraction (EBSD) and electron channeling contrast imaging (ECCI) were used to examine microstructural changes of the austenitic low-density Fe-30.5Mn-8.0Al-1.2C (8Al) and Fe-30.5Mn-2.1Al-1.2C (2Al) (wt.%) steels during cold rolling. As the strain increased, deformation mechanisms, such as stacking faults, slip, mechanical twinning, and shear banding were activated in both steels cold rolled up to strain of 0.69. Only slip was noted in these steels at low strain (e=0.11) and slip dominance was detected in the 8Al steel at higher strains. Shear banding became active at higher strain (e~0.7) in these materials. An inhomogeneous microstructure formed in both alloys at such strain level. More extensive mechanical twinning in the 2Al alloy than that in the 8Al alloy was observed. Fish bone-like structure patterns were revealed in the 8Al steel and a river-like structure in the 2Al steel. Detailed microstructure features as elongated and fragmented grains along the rolling direction (RD) were found for both steels, as already observed in other high-Mn steels. These deformed structures are composed by lamellar packets which can contain mechanical twins or slip lines and shear bands.
The Bond method for ball mil designing has been used for 60 years. Based on the Work Index test, such method is applied mostly in traditional circuit configuration, which includes multi-staged crushing, followed by rod and ball milling. On the other hand, simulation is a widespread and used technique for comminution, classification modeling, and simulation. Even though both methods are complementary, there is no effective integration between them. This work shows a technique designed to integrate both energy and modeling approaches for estimating and improving ball mill grinding performance. The work is based on industrial data survey results, as well as on laboratory testing, the latter developed specifically for such a purpose. The technique was validated under an industrial environment for assessing the obtained results.
The Pau Branco mine supplies two blast furnaces with iron ore lumps, and currently, charcoal consumption for pig iron production accounts for 47% of the blast furnaces' operational cost. A geometallurgical model is presented to support an economic study considering reserve volumes, product quality, and operational costs based on the metallurgical performance of different iron ore typologies. Sample analysis provides values required in the model. From the model, an alternative production plan is presented with a positive impact of USD 25.6M over the current net present value of the mining/mill system.
This study deals with the main environmental impacts and possible mitigation measures for many pipeline tracks, due to the mining of different substances in areas of interference between mining activities and mineral research and those resulting from construction and gas pipeline operation. By monitoring the identified interferences/disturbances, it was determined that although punctual and small in number, the extraction of mineral resources in the proximity of the gas pipelines could represent risks for the security of the undertaking. In general the risks are consequence either of the use of explosives or of induced erosive processes that could lead to pipeline instability. It is necessary to block the mining activities on both sides of the pipeline tracks in order to minimize risks to the pipeline, to others, to society, and to the environment. Also, the establishment of "flexible" track limits could be adopted in areas adjacent to the pipelines for the exploration of some mineral deposits, thus prioritizing security preservation with a minimum of socio-environmental impacts.
