Powder Materials Research Articles

Computer Simulation and Speedup of Solving Heat Transfer Problems of Heating and Melting Metal Particles with Laser Radiation

The study of the process of laser action on powder materials requires the construction of mathematical models of the interaction of laser radiation with powder particles that take into account the features of energy supply and are applicable in a wide range of beam parameters and properties of the particle material. A model of the interaction of pulsed or pulse-periodic laser radiation with a spherical metal particle is developed. To find the temperature distribution in the particle volume, the non-stationary three-dimensional heat conductivity equation with a source term that takes into account the action of laser radiation is solved. In the plane normal to the direction of propagation of laser radiation, the change in the radiation intensity obeys the Gaussian law. It is possible to take into account changes in the intensity of laser radiation in space due to its absorption by the environment. To accelerate numerical calculations, a computational algorithm is used based on the use of vectorized data structures and parallel implementation of operations on general-purpose graphics accelerators. The features of the software implementation of the method for solving a system of difference equations that arises as a result of finite-volume discretization of the heat conductivity equation with implicit scheme by the iterative method are presented. The model developed describes the heating and melting of a spherical metal particle exposed by multi-pulsed laser radiation. The implementation of the computational algorithm developed is based on the use of vectorized data structures and GPU resources. The model and calculation results are of interest for constructing a two-phase flow model describing the interaction of test particles with laser radiation on the scale of the entire calculation domain. Such a model is implemented using a discrete-trajectory approach to modeling the motion and heat exchange of a dispersed admixture.

Study on Polishing Technologies for Additive Manufacturing Parts

Additive manufacturing has a good application prospect in aerospace, medical implantation and other fields, but the molding surface quality is poor, without post processing can not meet the requirements of high service, polishing processing is a key link in the high-performance metal additive manufacturing technology chain. This paper summarizes the characteristics of the ladder effect, the high roughness of the forming surface. In recent years, additive manufacturing technology, also known as 3D printing, has been highly valued by aviation enterprises for its unique advantage in rapid prototyping, particularly for complex metal parts. However, due to the layer-by-layer growing process of 3D printing, the built parts often have poor surface roughness and are not suitable for practical use without post-treatment. Based on this foundation, the primary focus of research in the field of additive manufacturing for metal parts polishing includes electrochemical, laser, and abrasive flow polishing technologies. The progress in these areas is examined with consideration given to various manufacturing processes, different types of metal powder materials, and diverse structures (such as porous structure and high aspect flow channels) found in additive manufacturing samples. This review summarizes the research findings related to surface roughness, material removal, surface residual stress, profile accuracy retention, and other technical indicators associated with the polishing process for additive manufacturing metal parts. Finally, the paper discusses potential future developments in polishing technology for 3D printed metal parts.

Porosity effect on the thermal conductivity of sintered powder materials

In this work, the effective thermal conductivity of sintered powder materials is studied. The extensive literature related to the proposed models about this property in all kind of porous materials is reviewed, and a new equation is proposed as a function of the fully dense material conductivity, the porosity of the material and the tap porosity of the starting powder. This equation covers the porosity range of powder aggregates from the tap porosity to zero porosity, and also applies to sintered powders. The proposed equation has been experimentally validated by fitting to experimental data of metallic sintered powder materials measured at room temperature, resulting very good agreements. Also, alternative models proposed by other authors have been fitted to the same experimental data to check the relative goodness of the proposed model. The results allow to conclude that a percolation model can describe the behaviour of the effective thermal conductivity of sintered powder materials with low and medium porosity levels.

Synthesis of Y2O3 Oxide Dispersion-Strengthened Ti-6Al-2Sn-4Zr-2Mo Alloy Powder by In Situ Gas Atomization Method

Oxide dispersion-strengthened (ODS) alloys demonstrate enhanced mechanical properties at elevated temperatures and show potential as next-generation powder materials for additive manufacturing. These alloys can mitigate defects such as micropores and cracks by regulating solidification and grain growth behaviors during the additive manufacturing process. This study investigates the fabrication technology for ODS Ti-6Al-2Sn-4Zr-2Mo (Ti6242) alloy powder to achieve uniform oxide distribution within the alloy powders. Thermodynamic calculations were employed to determine the optimal Ti6242–Y2O3 composition for in situ gas atomization, ensuring complete dissolution of the oxide in the Ti6242 molten metal and subsequent reprecipitation upon cooling. A rod-shaped ingot was produced via vacuum arc melting, resulting in coarse Y2O3 precipitating along the grain boundaries. The powder was fabricated through an electrode induction gas atomization method, and the ODS Ti6242 powder exhibited a spherical shape and a smooth surface. Cross-sectional analysis revealed the uniform distribution of Y2O3 oxide particles, measuring several tens of nanometers in size, within the alloy powder. This research demonstrates the successful synthesis of oxide-integrated ODS Ti6242 alloy powder through the in situ gas atomization method, potentially advancing the field of additive manufacturing for high-temperature applications.

Research on the infiltration law and enhancing application of dust suppressants in powder materials

ABSTRACT Dust emissions from open-pit mining pose a significant threat to environmental safety and human health. Currently, the range of dust suppressants used in coal mining is limited, often failing to account for their suitability across various stockpiles. This oversight results in poor infiltration after application, leading to insufficient crust formation and reduced durability. To explore the permeability of dust suppressant solutions in different stockpiles and develop a broader range of suppressants, numerical simulations were conducted to analyze the effects of liquid properties on infiltration rates. The results showed that increased liquid surface tension promotes infiltration, whereas higher solid-liquid contact angles and liquid viscosity inhibit it. Building on these findings, experimental work was undertaken using a water-based polyurethane with strong adhesion and low viscosity, combined with xanthan gum and polyethylene glycol, to optimize the dust suppressant formulation. The optimal binder formulation was found to contain 1.5% water-based polyurethane, 0.2% xanthan gum, and 1% polyethylene glycol. Infiltration experiments revealed distinct infiltration patterns for the dust suppressant solution in both rock and coal dust. The appropriate dosage of surfactants was also determined. The study indicated that surfactants enhance wettability and significantly reduce the solution’s surface tension. For hydrophilic rock dust, moderate surfactant addition improves permeability, while excessive amounts disrupt capillary forces. In contrast, for hydrophobic coal dust, wettability governs infiltration, with surfactants enhancing this property. Based on these findings, dust suppressant solutions suitable for both rock and coal dust were formulated. The formulations demonstrated excellent permeability, consolidation effects, and water resistance, as validated by tests measuring wind erosion resistance, crust strength, and water erosion resistance. The significance of this research lies in its comprehensive exploration of dust suppressant efficacy within different particulate media and the factors influencing penetration performance, providing important guidance for industrial and environmental management. With the rapid pace of industrialization, dust generation poses a serious threat to both the environment and human health, making the development of effective dust suppressants increasingly critical. This study employs numerical simulations and experimental investigations to reveal the impact of various solution properties on penetration performance, particularly highlighting the application of a novel aqueous polyurethane binder, which demonstrates strong adhesive properties and low viscosity. Through optimization of the binder composition via orthogonal experiments, the research identifies optimal surfactant concentrations tailored for rock and coal dust, thereby enhancing the penetration and binding capabilities of the suppressants. This finding not only improves the performance of dust suppressants but also provides a scientific basis for practical applications, effectively reducing dust dispersion, improving air quality, and protecting the ecological environment. Furthermore, the study validates the effectiveness and durability of the developed suppressants through wind erosion resistance, crust strength testing, and water erosion experiments. This research offers practical solutions for the mining, construction, and related industries in controlling dust, while also providing reliable scientific support for policymakers in environmental protection. In summary, this study not only holds significant academic value but also offers actionable guidance for dust control and environmental conservation in real-world applications.

Research and engineering application of DED laser cladding repair for steam turbine XM-25 alloy LP blades

High-strength martensitic precipitation-hardening stainless steel XM-25, characterised by its high strength, high hardness, and good workability, has been utilised in engineering as the low-pressure last stage blade of steam turbines. However, it is beset by the issue of water erosion. This paper focuses on the restoration of large blade workpieces made of XM-25 material, employing directed energy deposition (DED) laser cladding with parent material powder. The parameters for laser cladding include laser power of 1300 W, movement speed of 500 mm/min, and powder feed rate of 15 g/min. The performance of the XM-25 alloy after laser cladding restoration is evaluated through non-destructive testing (PT, RT), tensile testing, hardness testing, metallographic analysis, fracture morphology analysis, residual stress measurement, and high-cycle fatigue testing. Results indicate that the material after laser cladding exhibits an ultimate tensile strength exceeding 1200 MPa, a yield strength above 1050 MPa, microhardness above 415 HBW, residual stress at approximately 30% of the base material, and a fatigue limit of 586.25 MPa – 95% higher than the base material. These findings confirm the effectiveness of the proposed DED laser cladding method for restoring XM-25 turbine blades, offering a viable engineering solution for mitigating and repairing water erosion in steam turbine components.

Development of 17-4 PH Stainless Steel for Low-Power Selective Laser Sintering.

Selective laser sintering (SLS) is one of the prominent methods of polymer additive manufacturing (AM). A low-power laser source is used to directly melt and sinter polymer material into the desired shape. This study focuses on the utilization of the low-power laser SLS system to successfully manufacture metallic components through the development of a metal-polymer composite material. In this study, 17-4 PH stainless powders are used and mixed with polyoxymethylene (POM) and high-density polyethylene (HDPE) to prepare the composite powder material. The polymeric mixture is removed during the thermal degreasing process and subsequent sintering results in a solid metallic component. Sinterit Lisa with a 5 W, 808 nm laser source is used to fabricate the green part. For the printing parameters of 140 °C, laser power of 35.87 mJ/mm2, and layer thickness of 100 μm, the printed samples achieved a maximum density of 3.61 g/cm3 and a complete shape. After sintering at 1310 °C for 180 min, the tensile strength of the shrunk sample is 605.64 MPa, the hardness is HRC 14.8, the average shrinkage rate is 22%, and the density is 7.57 g/cm3, which can reach 97% of the theoretical density. This process allows the use of a wide range of particle sizes that the usual AM technologies have, making it a low-cost, low-energy-consumption, high-speed AM technology.

High-Temperature Properties of Niobium- and Molybdenum-Doped γ-TiAl Powder Materials Produced Using Titanium Hydride

High-Temperature Properties of Niobium- and Molybdenum-Doped γ-TiAl Powder Materials Produced Using Titanium Hydride

Oscillatory nature in melt-gas-powder interactions during laser powder bed fusion process revealed by CFD-DEM coupled modelling

ABSTRACT The laser powder bed fusion (LPBF) process encompasses interactions between different material states, including melt, gas, and powder. While observational techniques can capture specific states, they cannot be combined to produce a comprehensive monitoring how they are mutually interacted. Thus, an integrated modelling approach is a crucial solution for revealing their interactions. This study investigates melt-gas-powder dynamics under varying laser scan speeds through a coupled CFD-DEM multiphase model. Findings reveal that metal vapour consistently transitions from an initialisation phase to a processing phase, exhibiting consistent behaviour in the former but varied responses in the latter. A relationship is identified between scan speed and vapour flow angle (VFA), with higher speeds broadening the VFA. Significantly, three oscillatory behaviours are observed: first, the oscillation of locally intensified pressure (LIP) sites on keyhole walls, where vapour ejection modes shift and may become periodic at intermediate scan speeds; second, the oscillation of two induced argon vortex flows with opposite swirling directions; and third, a simultaneously induced varying drag force on powder spatter. These oscillations clarify various spatter mechanisms, offer insights for process optimisation, and suggest implications for process stability. The study also proposes future research directions to further elucidate these mechanisms.

Advanced Solid Lubrication with COK-47: Mechanistic Insights on the Role of Water and Performance Evaluation.

Metal-organic framework (MOF) nanoparticles have attracted widespread attention as lubrication additives due to their tunable structures and surface effects. However, their solid lubrication properties have been rarely explored. This work introduces the positive role of moisture in solid lubrication in the case of a newly described Ti-based MOF (COK-47) powder. COK-47 achieves an 8.5-fold friction reduction compared to AISI 304 steel-on-steel sliding under room air. In addition, COK-47 maintains a similarly low coefficient of friction (0.1-0.2) on various counterbodies, including Al2O3, ZrO2, SiC, and Si3N4. Notably, compared to other widely studied MOFs (ZIF-8, ZIF-67) and 2D materials powder (MXene, TMD, rGO), COK-47 exhibits the lowest friction (≈0.1) under the same experimental settings. Raman spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy, energy dispersive X-ray spectroscopy, scanning electron microscope, and transmission electron microscopy indicate that the tribofilm is an amorphous film obtained by hydrolysis of COK-47 in the air with moisture. Density functional theory further confirms that water catalyzes the decomposition of COK-47, a crucial step in forming the tribofilm.This study demonstrates the idea of utilizing MOF and water-assisted lubrication mechanisms. It provides new insights into MOF applications in tribology and highlights interdisciplinary contributions of mechanical engineering and chemistry.

Feδ+ diaspora titanium dioxide and graphene: A study of conductive powder materials and coating applications.

Developing new conductive primers to ensure electrostatic spraying is crucial in response to the call for lightweight production of new energy vehicles. We report a stabilized material, Fe-T/G, of Fe-doped TiO2 composite graphene synthesized by a simple hydrothermal and electrostatic self-assembly method. The resistivity decreases from 0.9165Ω·cm to 0.0943Ω·cm for T/G. XPS and EPR confirm that Fe3+ is doped into the TiO2 lattice to generate OVs, and Feδ+ is introduced to activate the surrounding Fe-Ti active sites to break the obstruction of the Ti-O bond and build the Ti-O-C and Feδ+-O-C bonds between TiO2 and graphene to connect the two tightly. Multiple electron transfer channels promote Feδ+ impurity energy levels in the TiO2 valence and conduction bands to build electron leaping pathways, enhancing the electron transport ability. Based on this, Fe-T/G can be used as a conductive coating material to develop various insulator surfaces. With Fe-T/G powder material and PVDF, a conductive primer coating can be made and overlaid on a plastic plate to simulate actual applications. The resistance can still be maintained below 25Ω·cm. Through contact angle experiments, it has been confirmed that the superhydrophobic surface has a water contact angle of 142.8°, with self-cleaning potential.

Recycling of used powder materials for additive manufacturing by processing in an inductively coupled plasma

Recycling of used powder materials for additive manufacturing by processing in an inductively coupled plasma

Mechanism Insights Into High‐Performance Cu2+ Adsorption by ZIF‐8/PAN Nanocomposite Fibers: Coordination and Ion Exchange Dynamics

ABSTRACTThe accumulation of copper ions in the environment can devastate the ecological systems and threaten the health of organisms. Consequently, the development of effective adsorbents to extract Cu2+ from aqueous solutions is urgently needed. Here, the Zeolitic Imidazolate Framework‐8 (ZIF‐8)/polyacrylonitrile (PAN) nanocomposite fibers were synthesized by electrospinning and further characterized using X‐ray diffraction (XRD), scanning electron microscopy (SEM), and Fourier transform infrared spectroscopy (FTIR). ZIF‐8 powders were uniformly distributed on the surface of the nanocomposite fibers, and amide CONH bonds were formed between the NH2 groups of ZIF‐8 and the CO groups of PAN. The ZIF‐8/PAN nanocomposite fibers demonstrated an exceptional Cu2+ adsorption capacity of 275.7 mg g−1 at pH = 4.0. The adsorption process adhered to the pseudo‐second‐order kinetics and the Langmuir isotherm model. The adsorption mechanism, as conformed by FTIR and X‐ray photoelectron spectroscopy (XPS) analysis, involves the coordination of the NH2 and CO groups with Cu2+ and the ion exchange processes between Cu2+ and Zn2+ for the nanocomposite fibers. This study provides a novel approach for the removal of Cu2+ from aqueous solutions and addresses the challenge of recovering powder materials in wastewater treatment.

Синтез самоармованого порошкового матеріалу на основі високоентропійного сплаву

In this work, the formation of a self-reinforced HEA–WC powder material during the mechanical alloying (MA) of a mixture of elemental powders of the W-Fe-Co-Ni system in a planetary ball mill in a gasoline environment was investigated. X-ray diffraction (XRD), microstructural, and energy dispersive spectral (EDS) analysis revealed that after 20 hours of MA of the powders in a carbon-containing medium, a powder material based on a high-entropy alloy was formed. HEA based powder material contains two solid solutions with BCC and FCC crystal structure, as well as a carbide WC phase formed "in-situ" owing to the large negative value of the mixing enthalpy between carbon and tungsten. The “in-situ” formation of WC particles contributes to the enhancement of interfacial bonding with the metal matrix of the HEA. All phase components of the HEA–WC powder material are in the nanostructured state. The particles of the powder material have a close to spherical shape and a bimodal particle size distribution. The powder material consists of fine particles with a size of 1–10 μm and their agglomerates with a size up to 100 μm. The microstructure of the particles consists of the main gray phase of the BCC solid solution, dark spaces of the FCC solid solution and fine WC particles with a size of 0.1 μm to 1 μm evenly distributed in the HEA matrix. High-entropy alloys with the addition of carbon are promising in terms of practical application, because carbon, having a small atomic radius, dissolves as an interstitial element in the crystal lattice of the substitutional solid solutions of the HEA principal elements and, as a result, significantly affects their structure and phase composition, and, therefore, will contribute to the improvement of the mechanical properties of the self-reinforced powder material due to the effects of both solid-solution strengthening by interstitial atoms and the precipitation strengthening by the carbide phase particles.

Features of manufacturing case of hydraulic cylinders of structural powder steel

This work examines the dependence of the structure and properties of iron-based powder materials used for body parts of hydraulic cylinders on their composition and manufacturing technology. The role and importance of powder structural materials in industrial areas, the features of the production of parts for hydraulic devices and the characteristic features of methods for strengthening parts made from these materials are also explored here. During the research, powder materials containing Fe-Cu and Fe-Cu-graphite were used to prepare the hydraulic cylinder body part. The influence of the density and porosity of sintered materials on the physical properties of steam-processed powder material, the influence of the steam oxidation regime of parts made from powder material on the microstructure, mechanical and technological properties have been studied. The development of a technological process for producing iron-based powder materials and products made from them by cold pressing, sintering and steam-thermal oxidation makes it possible to improve the structure, physical, mechanical and technological properties of these materials. The results of this study highlight the importance of optimizing the composition of powder materials and processing conditions in order to develop more reliable and durable parts for hydraulic cylinders and other hydraulic devices, and also help to identify important parameters affecting properties.

Self-Organization of Surface Structures during Friction Coatings Based on Forsterite

In the work, the patterns of friction and wear of forsterite-based coatings were studied, and their structural-phase composition, conditions of formation and self-regulation of surface structures were determined from the standpoint of the structural-energy theory of friction. Detonation coatings developed on the basis of forsterite are characterized by high anti-friction properties. The conducted studies showed that the most appropriate application of the investigated coatings is to increase the reliability of operation of friction nodes during strengthening and restoration, for example, for moving pairs of control mechanisms, hinges of guide surfaces, cams, sliding supports, pairs with reciprocating movement, bearings, sliding guides, etc. in which the use of traditional lubricants is undesirable. Compounds of complex oxides of magnesium orthosilicate were used as the basis of composite coatings. The structural and phase composition of the coatings, the peculiarities of the formation of complex alloyed secondary structures, taking into account both the properties of the alloying elements and the structures formed by them, were established. The physical mechanism was determined and the main factors determining the level of thermodynamic graphitization were clarified. The studied self-lubricating compositions can be used both for strengthening and for high-quality restoration of worn triboelements by any technological methods using powder materials.

Influenced Nano and Micro Powder on Electrode Wear Rate in Electric Discharge Machining Process with RSM

Electric discharge machining (EDM) is considered one of the most favoured machining processes to produce many press tools and dies because of its good capability to manufacture complicated different shapes and machinability of very brittle and hard materials. This method has enabled the machining of all electrical conducting material. The method removes any metal with sparks that can be generated between the workpiece and the electrode tool. The material of electrode tool made of graphite or copper gradually makes the bore or cavity which is a like mirror image of the shape of the die tool. Therefore, is no any direct contact in the midst the surface of specimen and the electrode tool. Through the dielectric and by servo mechanism we can be controlled distance and the sparks flow at fluid. In this method, suitable the matter materials in Nano-grain powder are mixed together with the dielectric fluid. The same quantity percentage of transformer oil liquid and Nano and micro size graphite powder was mixed with utilized as the dielectric fluid in this study. This search goal is to analyse the response to some method variables parameters like current, Nano-powder focusing, pulse off time and pulse on the period especially in manufacturing (HSS) on the electrode wear rate (EWR). As maximum possible (EWR) was (36.890) mm3/min acquired at a Nano-powder focusing of pulse off time (55) µs (10)g/l, current (30)A and pulse on time (70) µs Empirical models are developed for TWR utilizing the analysis of variance (ANOVA) and regression models. The end results show that the suggested operation displayed an electrode wear rate 3.015 times greater than that of without putting Nano-powder. The proposed operation showed an increase amounting (EWR) by 66.84%.

Impact of oxygen content on debinding of binder jetted 17-4 PH stainless steel: Part I – Debinding

Binder jetting (BJT) utilises a sacrificial binder to shape green parts in a metal powder bed. The binder must be removed during debinding at elevated temperatures without contaminating the powder material. Efficient binder removal often requires oxygen in the atmosphere to aid the decomposition of the binder, but oxygen causes oxidation of the metal powders and hence negatively impacts the final material properties. Therefore, the use of tailored oxygen contents in the atmosphere during a standard debinding cycle performed at 300°C for 2 h was investigated for BJT printed 17-4 PH stainless steel. The change in bulk chemistry (carbon, oxygen, nitrogen, and hydrogen) from green parts to brown parts was thoroughly analysed and compared to the virgin powder subjected to the same conditions as used for debinding. While inert argon was beneficial for protecting the powder from oxidation, the removal of only ∼34% of binder was insufficient, resulting in 0.47 wt.% of residual carbon in the brown part. Debinding in atmospheres containing 3 vol.% O2 to 20 vol.% O2 led to almost complete binder removal, but also caused significant oxygen pickup by the powder between 1734 ppm and 1820 ppm. Furthermore, the brittleness of the brown parts increased, leading to undesirable powder losses during handling. The best debinding was obtained in Ar + 1 vol.% O2, which allowed the best combination of binder removal of ∼74% and lower oxygen pickup by the powder of 1617 ppm, together with sufficient brown part strength for handling.

High Speed Sintering of Polyamide 12: From Powder to Part Properties.

High Speed Sintering (HSS) is an additive manufacturing process with great potential to produce complex, high-quality polymer parts on an industrial scale. However, little information is currently available on the characteristics of the powder materials used and the part properties that can be achieved. This is also the case for the standard material polyamide 12 (PA 12) and the first commercially available HSS machine, the VX200 HSS. The aim of this study is, therefore, to provide the first comprehensive overview of the properties of PA 12 parts manufactured with the VX200 HSS and the characteristics of the PA 12 powder. This includes the analysis of the influence of part orientation and part position in the build job. To characterize the powder, particle size distribution, particle shape, thermal properties and powder flowability were analyzed. To characterize the parts, density and various thermal, mechanical and geometrical properties were analyzed. In summary, the powder material and part properties are largely similar to those of other Powder Bed Fusion of Polymer (PBF/P) processes. However, there are also significant differences for some part properties. It was also determined that the anisotropy of parts is very low compared to that of many other additive manufacturing processes.

Experimental investigation of surface roughness of liquid rocket engines parts manufactured with additive technologies

Modern development of additive manufacturing forms tasks of re-engineering of the existing design solutions and implementation of 3D printing technologies for new parts manufacturing. Nowadays, there is a large number of the process categories of “metal” additive manufacturing every of which is based on different principles and bears individual features. One of the most widely used process is a “single step” Powder Bed Fusion during which building parts are produced for a single operation. A focused laser beam is utilized as a heat source so that words collocation Laser Powder Bed Fusion (L-PBF) is used to address the process. L-PBF process is applied in the most different fields: aviation, space, biotechnical and other industries. One of the most appealing aerospace applications for production of complex parts of the liquid propellant rocket engines. A wide nomenclature of the available powder materials and relatively low requirements for technical level of equipment of the production site may be used for reasoning of the phenomena of growing popularity. One of the features of the L-PBF process is relatively high roughness of the produced surfaces which should be considered while designing of hydraulic tracts. There is a “stair-step effect” which contributes to roughness increase due to layer-based process which depends heavily on surface orientation during the building of the part, its location on the building plate, etc. Surface roughness of the L-PBF-manufactured parts is the subject of the experimental investigation of this work. The effect of the roughness change according to the part orientation and building direction is experimentally investigated on the test plates and inner surfaces of the swirl injectors specimens. All investigated specimens were built from Inconel 718. Four variants of the design types of swirl injectors specimens were investigated. The dependency of the roughness parameters versus inclination angle of the surface was obtained after the carried out analysis of the experimental data. Harmonic trigonometric dependencies are proposed for the roughness prediction. The proposed model accuracy is verified using Fischer criteria with =0.05.