Thermal and electronic properties of Bi1 − xSbx alloys

Polycrystalline Bi_1 ? xSb_x (x = 0.10, 0.12 and 0.15) semiconducting alloys were synthesized by mechanical alloying in order to achieve homogeneous thermoelectric materials with improved mechanical strength. The homogeneity of the powder samples were repeatedly checked by X-ray diffraction and scanning electron microscopy to standardize the milling conditions. The best possible homogenized material was developed with the milling conditions of BPR 30:1, ball diameter 30 mm, 400 rpm and milling time of 15 h. The electrical resistivity, thermoelectric power and thermal conductivity were measured in the temperature range 300–500 K. It was found through these experiments that the composition with x = 0.12 behaved in a normal semiconducting way, whereas the other two compositions (x = 0.10 and 0.15) showed degenerate semiconductor behaviour. These features have been qualitatively explained from the band structure and interband scattering mechanisms.     

Sintering behavior and non-linear properties of ZnO varistors processed in microwave electric and magnetic fields at 2.45 GHz

A study of the densification behavior and grain growth mechanisms of ZnO-based varistors composed of 98 mol.% ZnO–2 mol.% (Bi₂O₃, Sb₂O₃, Co₃O₄, MnO₂) has been carried out. The pressed samples were sintered in microwave electric (E) and magnetic (H) fields using a single-mode cavity of 2.45 GHz. The effect of the sintering temperature (900–1200 °C), holding time (5–120 min) and sintering mode (E, H) on the microstructure and electrical properties of the sintered varistor samples were investigated. The grain growth kinetics was studied using the simplified phenomenological equation Gⁿ = kte^(?Q/RT). The grain growth exponent (n) and apparent activation energy (Q) values were estimated for both electric and magnetic heating modes and were found to be n = 3.06–3.27, Q = 206–214 kJ mol^?1, respectively. The lower value of n estimated in the E field was attributed to a volume diffusion mechanism, whereas the higher n value in the H field sintering was correlated mainly to a combined effect of volume and surface diffusion processes. Samples sintered in the H and E fields showed high final densities. Moreover, the ones sintered in the H field presented slightly higher density values and bigger grains for all sintering temperatures than E field heated ones. The optimal sintering conditions were achieved at 1100 °C for a 5 min soaking time for both H and E field processed samples, where respectively densities of 99.2 ± 0.5% theoretical density (TD) and 98.3 ± 0.5% TD along with grain size values of G = 7.2 ± 0.36 μm and G = 6.6 ± 0.33 μm were obtained. Regarding the electrical properties, breakdown voltage values as high as 500–570 V mm^?1 were obtained, together with high non-linear coefficients α = 29–39 and low leakage currents (J_l ≈ 5 × 10^?3 mA cm^?2), respectively, for E and H field sintered varistor samples. Moreover, samples sintered in an H field systematically exhibited higher breakdown voltage values compared to the ones sintered in the E field. This was attributed to an improved coupling between the H field and the present dopants within the ZnO matrix, this latter being mostly semiconductive, thus leading to an enhanced reactivity and improved properties of the electrostatic barrier.     

Development of high DC-bias Mn–Zn ferrite working at frequency higher than 3 MHz

Modern high-frequency electronic technology demands Mn–Zn soft ferrite for high DC-bias and low power loss applications. In this study, DMR50B ferrite material with a very attractive DC-bias property and with a lower power loss at high frequency up to 3 MHz was developed employing a conventional ceramic powder processing technique based on our previous study of DMR50 material, indicating its magnetic properties can be further improved by microstructure homogeneity. The core loss is around 200 kW/m³ at 3 MHz, 10 mT and 100 °C, and only around 20 kW/m³ at 700 kHz, 30 mT and 100 °C; its cutoff frequency f_r is ～4 MHz and its incremental permeability μ_Δ remains constant until H_DC = 100 A/m. Furthermore, the electromagnetic characteristics and the microstructure of this new DMR50B material are also discussed.     

BiFeO3 thin films of (1 1 1)-orientation deposited on SrRuO3 buffered Pt/TiO2/SiO2/Si(1 0 0) substrates

BiFeO₃ (BFO) thin films of varying degrees of (1 1 1) orientation were successfully grown on SrRuO₃-buffered Pt/TiO₂/SiO₂/Si(1 0 0) substrates by off-axis radio-frequency magnetron sputtering. They demonstrate much enhanced ferroelectric behavior, including a much enhanced remnant polarization (2P_r ～ 197.1 μC cm^?2 at 1 kHz) measured by positive-up negative-down (PUND), at an optimized deposition temperature of 590 °C. The effects of film deposition temperature on the degree of (1 1 1) orientation, film texture, ferroelectric behavior, leakage current and fatigue endurance of the BFO thin films were systematically investigated. While the degree of (1 1 1) orientation is optimized at 590 °C, the defect concentration in the film increases steadily with increasing deposition temperature, as demonstrated by the dependence of leakage behavior on the deposition temperature. The polarization behavior is shown to strongly depend on the degree of (1 1 1) orientation for the BFO thin film. Oxygen vacancies are shown to involve in the conduction and dielectric relaxation of the BFO thin films deposited at different temperatures, as demonstrated by their dielectric and conduction behavior as a function of both temperature (in the range 294–514 K) and frequency (in the range 10^?1–10⁶ Hz).     

Manufacturing of Al–Mg–Si alloy foam using calcium carbonate as foaming agent

Aluminium foams can be manufactured by two main methods: casting and powder metallurgy. When the latter route is used, a foaming agent (usually TiH₂) is mixed with the aluminium or aluminium alloy powders, followed by powder mixture consolidation (usually hot extrusion) into a precursor and finally its foaming treatment. In this research, two calcium carbonate powders were used as foaming agents on an Al–Mg–Si (AA6061) alloy. Their different characteristics (particle size and chemical composition) modified the manufacturing process to achieve the final foam. AA6061 powders were then mixed with 10% calcium carbonate and, after cold isostatic pressing into green cylinders, hot extruded at different temperatures (475–545 °C). The foaming treatment was carried out in a furnace preheated to 750 °C using several heating times. The density changed from 2.03 to 2.10 g/cm³ after cold isostatic pressing to 2.64–2.69 g/cm³ in precursor materials obtained by hot extrusion. Foaming behaviour depends on the carbonate powder as well as the extrusion temperature. Thus, natural carbonate powder (white marble) produces a foam density close to 0.65 g/cm³ after a shorter time than when chemical carbonate is used. The foam structure showed a low degree of aluminium draining, no wall cell cracks and a good fine cell size distribution. Compressive strength of 6.11 MPa and 1.8 kJ/m³ of energy absorption were obtained on AA6061 foams with a density between 0.53 and 0.56 g/cm³.     

Formation of bulk metallic glasses in Cu45Zr48−xAl7REx (RE = La,Ce, Nd,Gd and 0 ≤ x ≤ 5 at.%)

We report a series of bulk metallic glass-forming alloys of compositions (Cu₄₅Zr_48−xAl₇RE_x, RE = La, Ce, Nd, Gd and 0 ≤ x ≤ 5 at.%). By using a conventional copper mold sucking method, alloys with diameters ranging from 5 to 10 mm can be readily solidified into an amorphous structure without detectable crystallites. The best glass-forming ability is obtained for the alloys Cu₄₅Zr₄₆Al₇RE₂. Possible effects of RE addition on the glass-forming ability are discussed. In addition, the compositional effect on mechanical properties of Zr–Cu–Al–Gd alloys is presented.     

Buckling behaviors and adhesion energy of nanostructured Cu/X (X = Nb,Zr) multilayer films on a compliant substrate

Two sets of Cu/Nb (face-centered cubic (fcc)/body-centered cubic) and Cu/Zr (fcc/hexagonal close-packed) nanostructured multilayer films (NMFs) have been prepared on a flexible polyimide substrate, with a wide range modulation period (λ) from 250 down to 5 nm. The mechanical properties of the two NMFs have been measured upon uniaxial tensile testing and the buckling behaviors have been systematically investigated as a function of λ. A significant difference in the bucking behaviors was found between the two NMFs, with the buckles in the Cu/Nb NMF being mostly cracked, while the buckles were nearly crack-free in the Cu/Zr NMF. The different buckling behaviors, dependent on the constituent phases, are rationalized in the light of the disparity in mechanical properties. The criteria to characterize buckle cracking have been discussed with respect to the mechanical properties (e.g. yield strength, ductility and fracture toughness) of the NMFs. A modified energy balance model has been employed to estimate the adhesion energy of the NMFs on the polyimide substrate. Within the λ regime below a critical size (λ_crit) of ～50 nm a λ-independent adhesion energy of about 1.1 and 1.2 J m^?2 has been determined for the Cu/Nb and Cu/Zr NMFs, respectively, which agrees well with previous reports on the metal film/polymer substrate systems. Within the λ regime greater than λ_crit, however, the measured adhesion energy exhibit a strong size effect, i.e. increasing with increasing λ. The λ dependence of the evaluated adhesion energy is discussed in terms of the size-dependent deformation mechanism in NMFs. A micromechanics model has been utilized to quantify the critical modulation period of ～50 nm, where the deformation mechanism changes from dislocation pile-up to confined layer slip.     

Cationic and radical polymerization of N-vinyl-2-phenylpyrrole: Synthesis of electroconducting,paramagnetic and fluorescent oligomers

Cationic polymerization of N-vinyl-2-phenylpyrrole (catalysts: Me₃SiCl, CF₃COOH, BF₃·OEt₂, HCl, WCl₆, FeCl₃, complex LiBF₄–dimethoxyethane, catalysts concentration 1–2 wt%, 20–70 °C, 24–48 h) affords oligomers (molecular weight 1400–1700) of a unexpected structure with alternating 2-phenylpyrrole and ethylydene units, the yields reaching 63%. The oligomers structure has been supported by isolation and identification of the corresponding dimer, N-vinyl-2-phenyl-5-[N-(2-phenyl-1H-pyrrol-1-yl)ethyl]-1H-pyrrole. Radical polymerization of the same monomer (AIBN, 1.5–4 wt%, 60–80 °C, 40–60 h or UV irradiation or both) gives oligomers (molecular weight 2100–3000) of normal structure having polyethene backbone with pendant 2-phenylpyrrole groups in up to 40% yields. The oligomers of both types are semiconductors (1.3 × 10^?6–3.6 × 10^?6 S/cm) after doping with I₂, paramagnetic (4.2 × 10¹⁷–8.7 × 10¹⁷ g^?1) and fluorescent in a near UV region (λ 355–363 nm, acetonitrile).     

Crystal and faceted dendrite growth of silicon near (1 0 0)

The crystal growth shape (CGS) and faceted dendrite growth of silicon near (1 0 0) are observed by in situ observation. The morphological transformations of the facets and curved orientations on the CGSs under different undercoolings (ΔT) are investigated, and the growth mechanism of the faceted dendrite is clarified. (1 1 0) facets with a low growth velocity and (1 0 0) curved interface with a relatively high growth velocity are observed on the crystal during the formation of silicon CGS, which shows a perfect foursquare shape dominated by (1 1 0) facets. At a relatively high ΔT, a faceted dendrite with a flat tip appears at the (1 1 0) facet of CGS. The (1 0 0) curved interface disappears with decreasing curvature. With increasing ΔT, both facet and curved interface growth velocities increase linearly, and the rate of curvature decrease increases. A two-dimensional image is developed to elucidate the growth mechanism of silicon 〈1 1 0〉 faceted dendrites near (1 0 0).     

Unidirectional solidification of Zn-rich Zn–Cu peritectic alloys—II. Microstructural length scales

Experimental results are presented of solidification microstructure length scales including η-phase cell spacing, primary ε secondary dendrite arm spacing, size of nonaligned dendrite of primary ε, and volume fraction of primary ε, as functions of alloy concentration (containing up to 7.37 wt% Cu) and growth velocity (ranging from 0.02 to 4.82 mm/s) in the unidirectional solidification of Zn-rich Zn–Cu peritectic alloys. Intercellular spacing (λ) of two-phase cellular structure decreases with increasing growth velocity (V) such that λV^1/2 is constant at a fixed alloy concentration in parametric agreement with the KGT and Hunt–Lu models. The value of λV^1/2 varies from 216±10 to 316±55 μm^3/2/s^1/2 with decrease in alloy concentration from 4.94 to 2.17 wt% Cu. These values are much greater than for normal eutectic systems but comparable with monotectic alloys. Dendritic secondary arm spacing (λ₂) of primary ε decreases with increasing V such that λ₂V^1/3 is constant ranging 14.9±0.9 to 75.6±8.1 μm^4/3/s^1/3 with increase in alloy concentration (C₀) from 2.17 to 7.37 wt% Cu, which is in parametric agreement with predictions of arm-coarsening theory. The volume fraction (f_ε) of primary ε increases with increasing V for Zn-rich Zn–3.37, 4.94 and 7.37 wt% Cu hyperperitectic alloys. Predictions of the Scheil and Sarreal–Abbaschian models show good agreement with the observed f_ε for Zn–4.94 wt% Cu at moderate V from 0.19 to 2.64 mm/s, but fail at low V of less than 0.16 mm/s and at high V of greater than 3.54 mm/s. The measured average size, Λ, of nonaligned dendrites of primary ε decreases with increasing V such that ΛV^1/2 is constant for a given alloy, increasing from (0.98±0.04)×10³ to (7.2±0.7)×10³ μm^3/2/s^1/2 with increase in alloy concentration from 2.17 to 4.94 wt% Cu.     

Mobility of nitrogen in ε-Fe3N below 150 °C: The activation energy for reordering

Previously quenched (from 573 K) ε-iron nitride powder of a composition close to Fe₃N, which shows partial disorder in the interstitial N superstructure, can be reordered by annealing between 373 and 408 K. The kinetics of the reordering can experimentally be traced by the axial ratio (c_hcp/a_hcp), as measured by X-ray powder diffraction, and can be described by a first-order rate law for the time-dependence of (c_hcp/a_hcp) with an Arrhenius-type temperature dependence of the rate constant. The determined activation energy of 144 ± 5 kJ mol⁻¹ can be associated with specific jumps of N atoms from disorder to order sites. The order-of-magnitude of the pre-exponential factor of (7 ± 10) × 10¹³ s⁻¹ can be related with the vibration frequency of the N atom in an octahedral site.     

Magnetic,electronic and thermodynamic properties of the heavy fermion compound CeNiAl4

We have carried out the magnetic susceptibility, electrical resistivity, specific heat, thermoelectric power and X-ray photoemission spectroscopy (XPS) measurements for CeNiAl₄. The magnetic susceptibilities have revealed a Curie–Weiss behavior above 30 K with a large negative paramagnetic Curie temperature θ_P = ?66 K and an effective moment of 2.45μ_B. The f-occupancy and the coupling between the f level and the conduction states are derived from XPS to be about 0.83 and ～40–64 meV, respectively. The valence state of the Ce ion is close to 3+. Extrapolation of the lowest temperatures range of C/T(T²) yields the electronic specific heat coefficient γ = 0.5 J mol^?1 K^?2. In combination with the thermoelectric power and resistivity data, a heavy fermion state is confirmed in CeNiAl₄.     

Structure of a new ternary compound with high magnesium content,so-called Gd13Ni9Mg78

The magnesium-rich composition Gd₁₃Ni₉Mg₇₈ was synthesized from its constituent elements in sealed tantalum tubes in an induction furnace. X-ray diffraction, electron probe microanalysis and dark-field transmission electron microscopy (TEM) images revealed a new compound with a composition ranging from Gd_10–15Ni_8–12Mg_72–78 and low crystallinity. In order to increase the crystallinity, different experimental conditions were investigated for numerous compounds with the initial composition Gd₁₃Ni₉Mg₇₈. In addition, several heat treatments (from 573 to 823 K) and cooling rates (from room temperature quenched down to 2 K h^?1) have been tested. The best crystallinity was obtained for the slower cooling rates ranging from 2 to 6 K h^?1. From the more crystallized compounds, the structure was partially deduced using TEM and an average cubic structure with lattice parameter a = 4.55 Å could be assumed. A modulation along both a¹ and b¹ axis with vectors of modulation q1 = 0.42a¹ and q2 = 0.42b¹ was observed. This compound, so-called Gd₁₃Ni₉Mg₇₈, absorbs around 3 wt.% of hydrogen at 603 K, 30 bars and a reasonable degree of reversibility is possible, because after the first hydrogenation, irreversible decomposition into MgH₂, GdH₂ and NiMg₂H₄ has been shown. The pathway of the reaction is described herein. The powder mixture after decomposition shows an interesting kinetics for magnesium without ball milling.     

Novel FePBNbCr glassy alloys “SENNTIX” with good soft-magnetic properties for high efficiency commercial inductor cores

According to a recent study, Fe-based glassy alloys are expected good soft-magnetic properties such as high saturation magnetization and lower coercive force. We focused on Fe-based glassy alloys and have succeeded in developing novel glassy Fe_97?x?yP_xB_yNb₂Cr₁ (x = 5–13, y = 7–15) alloys for an inductor material. The glassy alloy series of Fe_97?x?yP_xB_yNb₂Cr₁ (x = 5–13, y = 7–15) have high glass-forming ability with the large critical thickness of 110–150 μm and high B_s of 1.25–1.35 T. The glassy alloy powder with chemical composition Fe₇₇P_10.5B_9.5Nb₂Cr₁ exhibits an excellent spherical particle shape related to the lower melting point and liquid phase point. In addition, Fe–P–B–Nb–Cr powder/resin composite core has much lower core loss of 653–881 kW/m³, which is approximately 1/3 lower than the conventional amorphous Fe–Si–B–Cr powder/resin composite core and 1/4 lower than the conventional crystalline Fe–Si–Cr powder/resin composite core due to the lower coercive force of 2.5–3.1 A/m. Based on above results, the glassy Fe₇₇P_10.5B_9.5Nb₂Cr₁ alloy powder enable to achieve ultra-high efficient and high quality products in a commercial inductor. In fact, the surface mounted inductor using Fe–P–B–Nb–Cr powder/resin exhibits the high efficiency of approximately 2.0% compared with the conventional inductors made of the crystalline Fe–Si–Cr powder/resin composite core.     

High-field magnetization and specific heat of UCu2T3Al7 alloys where T = Cr,Mn and Fe(II)

The UCu₂T₃Al₇ alloys, where T = Cr, Mn and Fe, crystallize in the ThMn₁₂-type tetragonal structure. Earlier investigation of magnetic and electrical properties revealed their complex magnetic behavior except of the Cr compound, which is paramagnetic, whereas their electrical resistivity is weakly temperature dependent. At present we report on the magnetization measurements at 4.2 and 77 K in the steady magnetic field up to 14 T and in the pulsed field up to 34 T with a pulse duration of 10 ms at T = 4.2 K. These experiments confirmed paramagnetism of the Cr alloy and showed lack of saturation for the compounds of the Mn and Fe with the “saturation” magnetic moment amounting to 3.1 and 5.0 μ_B/f.u., respectively. In turn, the specific heat was measured in the temperature range 1.2–70 K in magnetic field μ₀H = 0 and 7 K using a home-made and fully automatic calorimeter. The investigation of the specific heat at temperature 2–300 K has been done using Quantum Design PPMS machine. The magnetic field does not in principle influence the obtained results, whereas the coefficient of the electronic specific heat, γ is strongly enhanced and amounts to 410, 330 and 150 mJ mol^?1 K^?2 for the Cr, Mn and Fe compounds, respectively.     

Doped polypyrrole for MAPLE deposition: Synthesis and characterization

The contribution deals with synthesis and characterization of conductive polypyrrole (PPY), which should be suitable for depositions of thin layers by Matrix Assisted Pulsed Laser Evaporation (MAPLE) method. The samples of doped PPY containing various organic dopants – (i) p-toluenesulfonic acid, (ii) dodecyl-benzenesulfonic acid, (iii) dioctyl-sulfosuccinic acid and (iv) camphorsulfonic acid – were synthesized by polymerization of pyrrole in acidic or neutral solution. Solubility of synthesized PPY and settlement time of PPY particles in water and dimethylsulfoxide – parameters critical for MAPLE method – were investigated. The composition of prepared PPY was verified by FTIR spectroscopy. Conductivity of the polymer in solid state was determined to be in range from σ = 2.6 × 10^?6 S cm^?1 to σ = 6.0 × 10^?2 S cm^?1. The optimal material for MAPLE deposition is PPY containing organic dopants (ii)–(iv), dissolved in DMSO matrix (solubility from 4.1% to 6.5% by weight and settlement time 140–240 h).     

Fabrication and characterization of bulk glassy Co40Fe22Ta8B30 alloy with high thermal stability and excellent soft magnetic properties

In this work, Co₄₀Fe₂₂Ta₈B₃₀ alloy as a new bulk metallic glass with a wide supercooled liquid region of 74 K and excellent soft magnetic properties was prepared by the powder metallurgy method. Glassy Co₄₀Fe₂₂Ta₈B₃₀ powders were obtained by ball milling of melt-spun glassy ribbons at a cryogenic temperature and subsequently consolidated by hot pressing into disk-shaped specimens 10 mm in diameter and 2 mm thick. It was found that the new glassy alloy exhibited the largest diameter compared with the other Co-based bulk metallic glasses produced in the well-known Co–Fe–Ta–B alloying system up to now. The influence of the consolidation time on the microstructure and magnetic properties of the bulk samples was investigated by X-ray diffraction, differential scanning calorimetry, vibrating sample magnetometry and Faraday magnetometry. The results indicate that the new alloy exhibits a long incubation time before crystallization upon annealing above the glass transition temperature: noticeably longer than for other known (Co,Fe)-based amorphous alloys. The glassy bulk sample consolidated for 600 s at 923 K had a relative density of 99.2%, a saturation magnetization of 46.6 A m² kg^?1, a Curie temperature of 425 K and a low coercivity of 6 A m^?1. In addition, the new bulk glassy alloy exhibited ultra-high hardness of 13.48 GPa. The mechanisms by which the thermal stability and incubation time prior to crystallization increase are explained in accordance with pair correlation function analysis.     

Growth and spectroscopic characteristics of Cr3+:CsAl(MoO4)2 crystal

This paper reports the growth and spectroscopic characteristics of Cr³⁺:CsAl(MoO₄)₂ crystal. A Cr³⁺:CsAl(MoO₄)₂ crystal with dimensions of 42 mm × 37 mm × 10 mm has been successfully grown from a flux of Cs₂Mo₃O₁₀ by the TSSG method. The absorption and emission spectra were investigated. The absorption cross sections σ_a are 5.05 × 10^?20 cm^?2 at 481 nm for the ⁴A₂ → ⁴T₁ transition and 3.06 × 10^?20 cm^?2 at 670 nm for the ⁴A₂ → ⁴T₂ transition of Cr³⁺ ions, respectively. The emission cross section σ_e of ⁴T₂ → ⁴A₂ transition is 4.27 × 10^?20 cm² at 818 nm and fluorescence lifetime is 21 μs. Based on the absorption and emission spectra, the crystal field strength Dq, the Racah parameters B and C, the effective phonon energy ?ω and the Huang–Rhys factor S were calculated. The investigated results show that Cr³⁺:CsAl(MoO₄)₂ crystal may be regarded as a potential tunable laser crystal material.     

Fabrication of W–20 wt.%Cu alloys by powder injection molding

W–20 wt.% Cu balls were fabricated by powder injection molding using a binder system consisted of paraffin wax, high density polyethylene, ethylene vinyl acetate and stearic acid. By optimizing the injection molding parameters, defect-free green parts were obtained. A two-step debinding process was employed to extract the binders in the molded samples. All soluble ingredients of the binders in the green parts were extracted during solvent debinding, and the residual binders can be removed in thermal debinding. The debound W–Cu samples were sintered in H₂ atmosphere at temperatures ranging 1050–1150 °C for 2 h. It was shown that relative density of the sintered W–Cu samples increases from 87.37% of the theoretical to 95.58% as sintering temperature rises from 1050 °C to 1150 °C. Microstructures of the molded, the debound and the sintered W–Cu samples were observed by scanning electron microscope, and the sintered W–Cu balls have fine and homogeneous microstructures. Maximum compressive strength of W–Cu balls with 8.5 mm diameter reaches 58 kN.     

Cladding of pre-blended Ti–6Al–4V and WC powder for wear resistant applications

In this paper, a cladding investigation to achieve uniform distribution of WC particles which is crack-free, non-porous and without delamination using a 2 kW IPG Ytterbium doped, continuous wave, fibre laser with 1070 nm wavelength was reported. The single track deposition of a pre-blended powder, 27 wt.% Ti–6Al–4V/73 wt.% WC with a particle size range of 40–120 μm was made on Ti–15V–3Cr–3Sn–3Al substrate using a co-axial nozzle and a standard powder feeding system. The laser cladding samples were subjected to various microstructure examinations, microhardness and micro-abrasion tests. The results revealed that the best clad layers were achieved at an energy density of 111.10 J.mm^?2, 15–18.3 mm.s^?1 traverse speed; (583–667) mg.s^?1 powder feed rate with substrate surface irradiated by laser beam raising its temperature to about 200 °C. This resulted in a uniform distribution of WC within the clad and the results obtained from SEM, EDS and XRD revealed that the WC particles experienced surface melting with some diffusion into the matrix, thus promoting excellent bonding with the matrix and the formation of titanium and tungsten carbides, which include TiC and W₂C. The emergence of β-Ti, TiC and W in the clad resulted in enhanced hardness values. The mean value of microhardness in clad matrix is 678 HV when measured from the top of a transverse cross section of the clad sample into the interface region with the Ti substrate which has a hardness of 396 HV. Wear tests indicated the wear resistance of the clad was seven times that of the Ti alloy substrate.