Effect of test temperature on tensile properties of α/β brass containing lead
01 Mar 2006-Materials Science and Technology (Taylor & Francis)-Vol. 22, Iss: 3, pp 363-367
TL;DR: In this article, the authors found that α/β brass with the composition of Zn-56·9Cu-3·5Pb (wt-%) were deformed to failure at constant initial strain rates ϵ of 1 × 10−4 and 1 ×10−2 s−1 in the temperature range of 297−973 K. This behavior is attributed to the liquid metal embrittlement owing to the presence of lead in this material.
Abstract: Tensile specimens of α/β brass with the composition of Zn–56·9Cu–3·5Pb (wt-%) were deformed to failure at constant initial strain rates ϵ of 1 × 10−4 and 1 × 10−2 s−1 in the temperature range of 297−973 K. Unlike the superplastic behaviour of α/β brass, this material was found to exhibit much lower ductility with the minimum values being 11·2 and 16·2% around 873 K at ϵ=1 × 10−4 s− 1 and 1 × 10−2 s−1 respectively. This behaviour is attributed to the liquid metal embrittlement owing to the presence of lead in this material. As biased by the embrittling effect, rather than thermally activated deformation process, the evaluation of ductility δ and strain rate sensitivity index m as a function of temperature suggests an anomalous relationship between δ and m.
TL;DR: A review of recent advances in modeling and testing of liquid metal embrittlement can be found in this paper, where the individual effects of wetting, crack initiation, and propagation are discussed.
Abstract: Significant advances in the study of liquid metal embrittlement have occurred since 2000 but there have been few reviews of the liquid metal embrittlement literature since that time. This review discusses recent advances in modeling and testing. Specific solid–liquid systems (including steel exposed to molten lead–bismuth and aluminum–gallium) are reviewed. Relationships between various studies are considered and the need for careful test protocols is emphasized. The individual effects of wetting, crack initiation, and propagation are discussed. Mechanisms of liquid metal embrittlement including interatomic and mass transport-based phenomena are analyzed.
TL;DR: In this article, the effect of post-weld heat treatment (PWHT) on joint properties of copper-zinc alloy (brass) and low carbon steel friction welded joints was described.
Abstract: This paper describes the effect of post-weld heat treatment (PWHT) on joint properties of copper–zinc alloy (brass) and low carbon steel friction welded joints. The as-welded joint obtained 100% joint efficiency and the brass base metal fracture without cracking at the weld interface, and had no intermetallic compound layer. The joint efficiency with PWHT decreased with increasing heating temperature and its holding time, and its scatter increased with those increasing parameters. When the joint was heat treated at 823 K for 360 ks, it did not achieve 100% joint efficiency and fractured between the weld interface and the brass base metal although it had no intermetallic compound. The cracking at the peripheral portion of the weld interface was generated through PWHT. The cracking was due to the dezincification and the embrittlement of the brass side during PWHT.
TL;DR: In this paper, microstructure and crystallographic texture evolution were investigated for the α-FCC and β-Ordered B2 phase individually to understand their underlying deformation mechanism, which is attributed to the formation of the β-banded structure.
Abstract: Two-phase α-β Brass was severe plastically deformed by equal channel angular pressing using route A up to four passes at 330 °C. The microstructure and crystallographic texture evolution were investigated for the α-FCC and β-Ordered B2 phase individually to understand their underlying deformation mechanism. Microstructural analysis reveals a decrease in the average grain size in both α- and β- phases from ~7 μm to ~1.5 μm, where most of the grain refinement took place up to 2nd pass. In α-phase, 111 11 2 ¯ type twins evolve during deformation that reduces the strain in the α-grains with successive passes. This also leads to the formation of ∑3 coincident site lattice boundaries. In β-phase, dislocation slip occurred, and grains get elongated along the shear direction. β-grains come together to develop small bands about ~15° to the extrusion direction (ED). These small β-bands are interconnected to form larger β-bands parallel to ED. In α-phase, weak texture components evolve at positions deviated from the ideal end orientations due to the presence of secondary β-phase and twinning due to the low stacking fault energy of the α-phase. In β-phase, characteristic ECAP texture components evolve and strengthen with consecutive passes. This is attributed to the formation of the β-banded structure.
TL;DR: In this article , the authors review the emergent innovative and sustainable material solutions in the manufacturing industry, in line with environmental regulations, by highlighting smart alloy design practices and promoting new and innovative approaches for material selection and manufacturing process optimization.
Abstract: The recent environmental/health and safety regulations placed restrictions of use of hazardous substances on critical manufacturing sectors and consumers’ products. Brass alloys specifically face a challenging issue concerning the elimination of lead (Pb) which has been a critical element affecting both the machinability and overall quality and efficiency of their manufacturing process. The adaptation of novel materials and processing routes in the green economy constitutes a crucial decision for competitive business and industry growth as a worldwide perspective with substantial industrial and social impact. This paper aims to review the emergent innovative and sustainable material solutions in the manufacturing industry, in line with environmental regulations, by highlighting smart alloy design practices and promoting new and innovative approaches for material selection and manufacturing process optimisation. In this review we analyse the processing, structure and machinability aspects of leaded brasses and underline the major guidelines and research methodologies required to overcome this technical challenge and further improve the mechanical properties and machinability of lead-free brass alloys. Various alloying and processing strategies were reviewed together with the most important failure types, as they were extracted from the existing industrial and technological experience, covering more than 20 years of research in this field.
••06 Nov 2008
TL;DR: A balanced mechanics-materials approach and coverage of the latest developments in biomaterials and electronic materials, the new edition of this popular text is the most thorough and modern book available for upper-level undergraduate courses on the mechanical behavior of materials as discussed by the authors.
Abstract: A balanced mechanics-materials approach and coverage of the latest developments in biomaterials and electronic materials, the new edition of this popular text is the most thorough and modern book available for upper-level undergraduate courses on the mechanical behavior of materials To ensure that the student gains a thorough understanding the authors present the fundamental mechanisms that operate at micro- and nano-meter level across a wide-range of materials, in a way that is mathematically simple and requires no extensive knowledge of materials This integrated approach provides a conceptual presentation that shows how the microstructure of a material controls its mechanical behavior, and this is reinforced through extensive use of micrographs and illustrations New worked examples and exercises help the student test their understanding Further resources for this title, including lecture slides of select illustrations and solutions for exercises, are available online at wwwcambridgeorg/97800521866758
22 Dec 2003
TL;DR: In this paper, the second-rank tensors of a tensor were modeled as tensors and they were used to model the deformation of polycrystalline materials and their properties.
Abstract: Chapter 1. Introduction.1.1 Strain1.2 Stress.1.3 Mechanical Testing.1.4 Mechanical Responses to Deformation.1.5 How Bonding Influences Mechanical Properties.1.6 Further Reading and References.1.7 Problems.Chapter 2. Tensors and Elasticity.2.1 What Is a Tensor?2.2 Transformation of Tensors.2.3 The Second Rank Tensors of Strain and Stress.2.4 Directional Properties.2.5 Elasticity.2.6 Effective Properties of Materials: Oriented Polycrystals and Composites.2.7 Matrix Methods for Elasticity Tensors.2.8 Appendix: The Stereographic Projection.2.9 References.2.10 Problems.Chapter 3. Plasticity.3.1 Continuum Models for Shear Deformation of Isotropic Ductile Materials.3.2 Shear Deformation of Crystalline Materials.3.3 Necking and Instability.3.4 Shear Deformation of Non Crystalline materials.3.5 Dilatant Deformation of Materials.3.6 Appendix: Independent Slip Systems.3.7 References.3.8 Problems.Chapter 4. Dislocations in Crystals.4.1 Dislocation Theory.4.2 Specification of Dislocation Character.4.3 Dislocation Motion.4.4 Dislocation Content in Crystals and Polycrystals.4.5 Dislocations and Dislocation Motion in Specific Crystal Structures.4.6 References.4.7 Problems.Chapter 5. Strengthening Mechanisms.5.1 Constraint Based Strengthening.5.2 Strengthening Mechanisms in Crystalline Materials.5.3 Orientation Strengthening.5.4 References.5.5 Problems.Chapter 6. High Temperature and Rate Dependent Deformation.6.1 Creep.6.2 Extrapolation Approaches for Failure and Creep.6.3 Stress Relaxation.6.4 Creep and Relaxation Mechanisms in Crystalline Materials.6.5 References.6.6 Problems.Chapter 7. Fracture of Materials.7.1 Stress Distributions Near Crack Tips.7.2 Fracture Toughness Testing.7.3 Failure Probability and Weibull Statistics.7.4 Mechanisms for Toughness Enhancement of Brittle Materials.7.5 Appendix A: Derivation of the Stress Concentration at a Through Hole.7.6 Appendix B: Stress Volume Integral Approach for Weibull Statistics.7.7 References.7.8 Problems.Chapter 8. Mapping Strategies for Understanding Mechanical Properties.8.1 Deformation Mechanism Maps.8.2 Fracture Mechanism Maps.8.3 Mechanical Design Maps.8.4 References.8.5 Problems.Chapter 9. Degradation Processes: Fatigue and Wear.9.1 Cystic Fatigue of materials.9.2 Engineering Fatigue Analysis.9.3 Wear, Friction, and Lubrication.9.4 References.9.5 Problems.Chapter 10. Deformation Processing.10.1 Ideal Energy Approach for Modeling of a Forming Process.10.2 Inclusion of Friction and Die Geometry in Deformation Processes: Slab Analysis.10.3 Upper Bound Analysis.10.4 Slip Line Field Analysis.10.5 Formation of Aluminum Beverage Cans: Deep Drawing, Ironing, and Shaping.10.6 Forming and Rheology of Glasses and Polymers.10.7 Tape Casting of Ceramic Slurries.10.8 References.10.9 Problems.Index.
•28 Jan 1997
TL;DR: Superplastic forming and diffusion bonding as mentioned in this paper are two possible superplasticity mechanisms for high-temperature deformation and phenomenological relations for fine-structure super-plastic.
Abstract: Preface 1. Introduction 2. Key historical contributions 3. Types of superplasticity 4. Mechanisms of high-temperature deformation and phenomenological relations for fine-structure superplasticity 5. Fine-structure superplastic metals 6. Fine-structure superplastic ceramics 7. Fine-structure superplastic intermetallics 8. Fine-structure superplastic composites and laminates 9. High-strain-rate superplasticity 10. Ductility and fracture in superplastic materials 11. Internal-stress superplasticity (ISS) 12. Other possible superplasticity mechanisms 13. Enhanced powder consolidation through superplastic flow 14. Superplastic forming and diffusion bonding 15. Commercial examples of superplastic products Index.
TL;DR: The relationship between stress and strain rate is often sigmoidal in superplastic materials, with a low strain rate sensitivity at low and high strain rates (regions I and III, respectively) and a high strain rate sensitive at intermediate strain rate (region II) where the material exhibits optimal super-plasticity as discussed by the authors.
Abstract: The relationship between stress and strain rate is often sigmoidal in superplastic materials, with a low strain rate sensitivity at low and high strain rates (regions I and III, respectively) and a high strain rate sensitivity at intermediate strain rates (region II) where the material exhibits optimal superplasticity This relationship is examined in detail, with reference both to the conflicting results reported for the Zn-22 pct Al eutectoid alloy and to the significance of the three regions of flow
01 Jan 1989
TL;DR: The superplasticity in metals and ceramics, it will really give you the good idea to be successful as discussed by the authors, it is not only for you to be success in certain life you can be successful in everything, success can be started by knowing the basic knowledge and do actions.
Abstract: By reading, you can know the knowledge and things more, not only about what you get from people to people. Book will be more trusted. As this superplasticity in metals and ceramics, it will really give you the good idea to be successful. It is not only for you to be success in certain life you can be successful in everything. The success can be started by knowing the basic knowledge and do actions.