Explosive-driven Shock Wave Demagnetization of Nd2Fe14B Hard Ferromagnets
-
Junying Wu
,
Lang Chen
Abstract
Magnetic materials subjected to shock wave compression will undergo shock wave demagnetization. To further investigate the demagnetization performance of Nd2Fe14B ferromagnets, an open magnetic circuit cylinder was used as the energy-carrying body. The discharge process and circuit characteristics during shock wave demagnetization were analyzed. A series of the shock wave demagnetization tests were performed using the shock wave from the detonation of high explosives acting along the axial direction of the cylindrical magnets. The induced electromotive force and current were measured. The results indicate that Nd2Fe14B ferromagnet begins to demagnetize at approximately 0.28 μs after the shock wave enters its body. The induced electromotive force and current in coils are caused by the destruction of the magnetism in the smallest units of magnetic domains rather than the mechanical damage of the magnet structure. The influence of the shock wave pressure on the effect of demagnetization was investigated by altering the pressure of the shock wave acting the magnets. The results show that Nd2Fe14B ferromagnets can be absolutely demagnetized and destroyed by a high shock wave pressure, and that demagnetization is insufficient under a low 13 GPa shock wave pressure. In order to reduce eddy current losses during the process of the shock wave demagnetization, a new design of a split magnet with insulation layers was proposed. This process is very effective and beneficial to improve the energy conversion during the shock wave demagnetization.
©2012 by De Gruyter
Articles in the same Issue
- Preface
- Multi-Thickness Target Plate Impact Experimental Approach to Failure Waves in Soda-lime Glass and Its Numerical Simulation
- Orientation-dependent Constitutive Model with Nonlinear Elasticity for Shocked β-HMX Single Crystal
- Numerical Simulation of a Shock Tube for Bio-dynamics Study
- Explosive-driven Shock Wave Demagnetization of Nd2Fe14B Hard Ferromagnets
- Large Mass Protection with Close-celled Metallic Foams Under Low Velocity Impact: Spring-damper-foam Collision Model
- Performance Analysis and Optimization of a Dual Warhead System
- Establishment of a Dynamic Mohr–Coulomb Failure Criterion for Rocks
- Nonlinear Damage and Failure Behavior of Brittle Rock Subjected to Impact Loading
- Experiments and Modeling of Failure and Fragmentation of Alumina Cylinders under Uniaxial Compression
- Radiation Characteristics of a Reflector Antenna Under Shock Wave Loading
- Experimental and Numerical Study on the Dynamic Buckling of Ping-pong Balls under Impact Loading
- Dynamic Buckling of Cylindrical Shells under Axial Impact in Hamiltonian System
- A Microscopic Approach to Strain-rate Effect on the Compressive Strength of Concrete-like Materials
- Frontmatter
- Preface
- Multi-Thickness Target Plate Impact Experimental Approach to Failure Waves in Soda-lime Glass and Its Numerical Simulation
- Orientation-dependent Constitutive Model with Nonlinear Elasticity for Shocked β-HMX Single Crystal
- Numerical Simulation of a Shock Tube for Bio-dynamics Study
- Explosive-driven Shock Wave Demagnetization of Nd2Fe14B Hard Ferromagnets
- Large Mass Protection with Close-celled Metallic Foams Under Low Velocity Impact: Spring-damper-foam Collision Model
- Performance Analysis and Optimization of a Dual Warhead System
- Establishment of a Dynamic Mohr–Coulomb Failure Criterion for Rocks
- Nonlinear Damage and Failure Behavior of Brittle Rock Subjected to Impact Loading
- Experiments and Modeling of Failure and Fragmentation of Alumina Cylinders under Uniaxial Compression
- Radiation Characteristics of a Reflector Antenna Under Shock Wave Loading
- Experimental and Numerical Study on the Dynamic Buckling of Ping-pong Balls under Impact Loading
- Dynamic Buckling of Cylindrical Shells under Axial Impact in Hamiltonian System
- A Microscopic Approach to Strain-rate Effect on the Compressive Strength of Concrete-like Materials
Articles in the same Issue
- Preface
- Multi-Thickness Target Plate Impact Experimental Approach to Failure Waves in Soda-lime Glass and Its Numerical Simulation
- Orientation-dependent Constitutive Model with Nonlinear Elasticity for Shocked β-HMX Single Crystal
- Numerical Simulation of a Shock Tube for Bio-dynamics Study
- Explosive-driven Shock Wave Demagnetization of Nd2Fe14B Hard Ferromagnets
- Large Mass Protection with Close-celled Metallic Foams Under Low Velocity Impact: Spring-damper-foam Collision Model
- Performance Analysis and Optimization of a Dual Warhead System
- Establishment of a Dynamic Mohr–Coulomb Failure Criterion for Rocks
- Nonlinear Damage and Failure Behavior of Brittle Rock Subjected to Impact Loading
- Experiments and Modeling of Failure and Fragmentation of Alumina Cylinders under Uniaxial Compression
- Radiation Characteristics of a Reflector Antenna Under Shock Wave Loading
- Experimental and Numerical Study on the Dynamic Buckling of Ping-pong Balls under Impact Loading
- Dynamic Buckling of Cylindrical Shells under Axial Impact in Hamiltonian System
- A Microscopic Approach to Strain-rate Effect on the Compressive Strength of Concrete-like Materials
- Frontmatter
- Preface
- Multi-Thickness Target Plate Impact Experimental Approach to Failure Waves in Soda-lime Glass and Its Numerical Simulation
- Orientation-dependent Constitutive Model with Nonlinear Elasticity for Shocked β-HMX Single Crystal
- Numerical Simulation of a Shock Tube for Bio-dynamics Study
- Explosive-driven Shock Wave Demagnetization of Nd2Fe14B Hard Ferromagnets
- Large Mass Protection with Close-celled Metallic Foams Under Low Velocity Impact: Spring-damper-foam Collision Model
- Performance Analysis and Optimization of a Dual Warhead System
- Establishment of a Dynamic Mohr–Coulomb Failure Criterion for Rocks
- Nonlinear Damage and Failure Behavior of Brittle Rock Subjected to Impact Loading
- Experiments and Modeling of Failure and Fragmentation of Alumina Cylinders under Uniaxial Compression
- Radiation Characteristics of a Reflector Antenna Under Shock Wave Loading
- Experimental and Numerical Study on the Dynamic Buckling of Ping-pong Balls under Impact Loading
- Dynamic Buckling of Cylindrical Shells under Axial Impact in Hamiltonian System
- A Microscopic Approach to Strain-rate Effect on the Compressive Strength of Concrete-like Materials
