Search results for " Forging"
showing 10 items of 14 documents
TITAFORM - Precision Hot Forming, development of innovative hot-forming processes of aeronautical components in Ti-alloy with low buy/fly ratio: an I…
2012
In the paper the description of the project TITAFORM is provided. The project has been financed on the call "PON Linea 1" of the Italian government and represents an effective example of cooperation between academy and industry. The project is focused on the beta forging and hot stretch forming operations of titanium alloys. �� 2012 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.
Optically Forged Diffraction-Unlimited Ripples in Graphene
2018
In nanofabrication, just as in any other craft, the scale of spatial details is limited by the dimensions of the tool at hand. For example, the smallest details for direct laser writing with far-field light are set by the diffraction limit, which is approximately half of the used wavelength. In this work, we overcome this universal assertion by optically forging graphene ripples that show features with dimensions unlimited by diffraction. Thin sheet elasticity simulations suggest that the scaled-down ripples originate from the interplay between substrate adhesion, in-plane strain, and circular symmetry. The optical forging technique thus offers an accurate way to modify and shape two-dimens…
Beta-forging of Ti6Al4V titanium alloy powders consolidated by HIP: Plastic flow and strain-rate relation
2014
Ti6Al4V is probably the best known and studied titanium alloy, not only for aerospace applications. Nevertheless the deformation behavior still represents a challenge if any modification in the deformation process is required or introduced. This work deals with deformation behavior description of Ti6Al4V HIPped powders during high temperature deformation tests carried on in the Beta-region. Laboratory compression and tensile tests have been coupled with relaxation tests in order to achieve robust data about strain rate sensibility m-coefficient and activation energy Q. These results have been fitted for the assessment of a more general exponential deformation law. The final result is a “Dor…
Hot Impression Die Forging Process: An Approach to Flash Design for Tool Life Improvement
2005
In impression die forging the role of the flash geometry is fundamental since a proper design of the flash land strongly influences both the complete die filling and the die wear (i.e. the die life and the related costs). In this paper an integrated approach between numerical simulations and statistical tools was developed with the aim to optimize flash thickness in order to reduce die wear and to minimize material wasting. As wear is regarded, an analytical model depending on sliding velocity, temperature, die hardness and contact pressure was utilized during the numerical simulations of the process in order to reach a wear evaluation for different values of the flash design variables. Thu…
Mechanical and microstructural characterization of titanium gr.5 parts produced by different manufacturing routes
2022
Abstract In recent years, the aircraft industry has shifted its preference for metal parts to titanium and its alloys, such as the high-strength Titanium Grade5 alloy. Because of Titanium Grade 5 limited formability at ambient temperature, forming operations on this material require high temperatures. In these conditions, a peculiar microstructure evolves as a result of the heating and deformation cycles, which has a significant impact on formability and product quality. On the other hand, additive manufacturing technologies, as selective laser melting and electron beam melting, are increasingly being used and are replacing more traditional approaches such as machining and forging. Fundamen…
Dual phase titanium alloy hot forging process design: experiments and numerical modeling
2015
Titanium alloys are considered desirable materials when both good mechanical properties and weight reduction are required at the same time. This class of materials is widely used in those fields (aeronautics, aerospace) in which common steels and light-weight materials, e.g., aluminum alloys, are not able to satisfy all operative service conditions. During the last decade, forging of titanium alloys has attracted greater attention from both industrial and scientific/academic researchers because of their potential in providing a near net shaped part with minimal need for machining. In this paper, a numerical model of the forging sequences for a Ti-6Al-4V titanium alloy aerospace component is…
The role of the effect of manufacturing tolerances on a tubular linear ferrite motor
2015
Electric machines are often designed without considering workmanship and materials tolerances. Their manufacturing process involves a series of steps, starting with raw materials and ending with the machine assembly. In each of these steps occur deviations due, for instance, to mistakes in positioning tools or to the tolerances in the electrical and magnetic characteristics of the materials. These deviations may cause unwanted parasitic effects such as torque ripple, losses or acoustic noise. Such effects have to be considered especially in machines used in industrial drives for high performance applications. Moreover the tolerances in the magnetic materials have a considerable effect on th…
Influence of geometrical ratios in forgeability of complex shapes during hot forging of Ti-6Al-4V titanium alloy
2014
Abstract Titanium alloys are considered desirable materials when both mechanical properties and weight reduction are requested at the same time. This class of materials is widely used in application fields, like aeronautical, in which common steels and light-weight materials, like aluminum alloys, are not able to satisfy all operative service conditions. Most of manufacturing processes of titanium alloy components are based on machining operations, which allow obtaining very accurate final shapes but, at the same time, are affected by several disadvantage like material waste and general production costs. During the last decade, the forging processes for titanium alloys have attracted greate…
Beta forging of Ti-6Al-4V: Microstructure evolution and mechanical properties
2013
Titanium alloys are finding an increasing use in the aeronautical field, due to their characteristics of high mechanical properties, lightness and corrosion resistance. Moreover these alloys are compatible with the carbon fibre reinforced plastics that are also finding a wide use in the aeronautical field. On the other hand the use of these alloys implies some drawbacks, for example titanium alloys are often considered more difficult to form and generally have less predictable forming characteristics than other metallic alloys such as steel and aluminum. In this paper was studied both the microstructure evolution and the mechanical properties of a Ti-6Al-4V rolled bar after hot forging. The…