To date, slicing algorithms for additive manufacturing is the most effective for favourable triangular mesh topologies; worst-case models, where a large percentage of triangles intersect each slice plane, take significantly longer to slice than a like-for-like file. In larger files, this results in a significant slicing duration, when models are both worst cases and contain more than 100,000 triangles

Manufacturers using additive manufacturing to build parts need to know how the complex thermal histories imparted by rapid heating and cooling affect the homogeneity of the microstructure and mechanical properties within their parts. To identify the possible differences for a part built via powder bed fusion, a simulation incorporating superlayers was used to predict the thermal history for a part

Manufacturing industry has paid more attention to the carbon footprint in the manufacturing process with an increasing focus on ecological environment. Also, optimum machining parameters are usually considered as an efficient solution for minimizing carbon footprint and processing time owing to their great role in process control. To make a better process parameter set, a novel multi-objective parameter

The conventional theoretical method to calculate deformations and stress states is only limited to a few cases of simple extrusion dies due to a number of assumptions and simplifications. A coupled thermal-structural modelling framework incorporating finite element method is thus developed and implemented to determine the mechanical performances of the complicated spiral mandrel die, which has a complex

The funding note is missing in the paper. The funding note to add is the following: Open access funding provided by Technical Research Centre of Finland (VTT).

Optimization of the end milling process is a combinatorial task due to the involvement of a large number of process variables and performance characteristics. Process-specific numerical models or mathematical functions are required for the evaluation of parametric combinations in order to improve the quality of the machined parts and machining time. This problem could be categorized as the offline

Iron aluminides are intermetallic Fe–Al alloys known for their high temperature corrosion and oxidation resistance, which makes them candidate materials for high temperature applications. In the present work, the formation of an iron aluminide layer on a mild steel substrate by friction stir surfacing of aluminium alloy AA6351 followed by isothermal heat treatment is reported. After Al-alloy deposition

Non-traditional warehouses rise as effective solutions to shorten the travelled distances to store and retrieve unit loads, adding aisles crossing the parallel racks. Multiple warehouse configurations are proposed by the literature discussing the enhancements toward standard layouts. In previous contributions, the authors introduced the diagonal cross-aisle model, concluding about its positive impact

The successful realization of Industry 4.0 depends much on how coherently the cyber and physical realms are conjoined in cyber-physical systems. In the context of the fourth industrial revolution, research efforts have mostly been channeled toward the cyber domain, whereas the physical domain has received significantly lesser consideration. A physical domain generally comprises material shaping equipment

This study aims to investigate the effects of dry, minimum quantity lubrication (MQL), and nanofluid cutting conditions on surface roughness (Ra) and material removal rate (MRR) for Al6082-T6. Three controllable factors, namely, feed rate (Fr), spindle speed (Vs), and depth of cut (Dc) are studied at three levels using Taguchi method. Single-response optimization is conducted using S/N ratio and contour

Lapping ceramic balls with variable-radius groove plate (VRGP) has obvious advantages in achieving good consistency of batch manufacturing of ceramic balls. The material removal model of a single ball was established based on Hertz contact theory. Then, combining the previous research works based on kinematic analysis and the material removal model, the forming process of single ball was simulated

The original version of this article contained mistakes.

The direct laser metal deposition (DLMD) is an emerging technology in the additive manufacturing field, which is becoming widely adopted in several industrial applications. The optimal selection of process parameters is critical, given the cost of physical tests and the requirement for high-quality manufacturing. Correct forecasting of process parameters using predictive physical models is a viable

The main purpose of the present paper is to study the cutting parameter optimization technology by combining the response surface methodology (RSM) with the improved teaching–learning-based optimization (ITLBO) algorithm to obtain the best cutting parameters under multi-objective conditions. Considering the factors of cutting parameters which affect cutting force and surface roughness such as cutting

The welding of spatial intersecting curves is widely used in the pressure vessels, in which the welding quality cannot be achieved by traditional methods. To this end, this paper proposes a novel methodology of dual-robot welding for the intersecting pipes by means of motion planning and off-line programming. This method takes advantage of the redundancy of the dual-robot system to obtain alternative

Efficiency of coin manufacturing is often limited by the service life of the stamping dies, whose degradation by wear results in decreasing the quality of the produced coin engraving. The aim of this work is to explore the ability of the combined application of experimental characterization and numerical simulation of the material elastoplastic forming response, friction effects, and die material wear

Vegetable oil–based nanofluid minimum quantity lubrication (VNMQL) and tool surface microstructure can be employed to efficiently improve the cutting process in an environmentally friendly way. Biomimetics-based integration of VNMQL and tool surface microstructure is expected to have beneficial effects on the friction coefficient, the cutting force, the tool temperature, the tool wear, and the surface

Tool wear monitoring is a major concern in securing surface quality of workpieces and performance of the machining process. Most existing tool wear monitoring techniques seem to have looked at places other than the tool itself for solution or simply inapplicable in the highly automated industries. With insights from these techniques, this paper thus proposes an image-processing-based tool wear monitoring

During machining processes, a high temperature is generated in the cutting zone due to plastic deformation, resulting in an increase of wear and consequently reducing the lifetime of cutting tools. The addition of well-defined patterned surfaces with random or regular microfeatures to cutting tools can improve its wettability, providing an enhanced lubrication effect, a reduced tool-chip friction and

This study explores the feasibility of reusing waste quarry dust as a coating material for surface modification of tungsten carbide cobalt (WC-Co) using electrical discharge coating (EDC). The main objective is to investigate the effect of quarry dust suspension with different concentrations (0–40 g/l) on the characteristics of coated surface such as coating layer thickness, coating element composition

Electrohydraulic forming (EHF) is one of the high-velocity metal forming processes that can significantly increase the formability of metals compared with quasi-static forming processes. On the other way, multi-point forming (MPF) is one of the flexible forming methods that provides different sheet metal geometries by varying the height of the pins. The purpose of this study is to take the advantages

This work provides an in-depth investigation of the influence of laser energy density on the mechanical, surface, and dimensional properties of carbon fiber-reinforced PA12 parts manufactured by selective laser sintering (SLS). A space-filling design of experiments (DOE) was used to conduct the experimental trials to cover a wide range of laser sintering parameters. The consolidation mechanism was

Advanced welding processes for structural materials are gaining increasing importance for strategic applications in nuclear, aerospace, automobile, and defence sectors. These processes have been designed keeping in view the criterion of minimal stress generation, microstructure retentivity, and process reproducibility. Narrow gap laser welding (NGLW) is one such advanced welding technique that has

Aiming at the problem of low efficiency in cutting silicon crystals with traditional wire electrical discharge machining (wire EDM) equipment, this paper proposes a method to improve the efficiency of electrical discharge cutting for silicon crystals by using composite pulse power to process semiconductors. This paper established a wire EDM equivalent circuit model, analyzed the magnitude of the discharge

The objective of this work is to tackle the challenges of monitoring and detecting subtle process changes in chemical mechanical planarization (CMP), an ultraprecision manufacturing process. Monitoring ultraprecision processes is usually of difficulty due to their innate complexity and low signal-to-noise ratio in sensor signals. Especially for subtle signal variations during small process changes

This paper presents a novel indirect cryogenic cooling system, employing liquid nitrogen (LN2) as a coolant for machining the difficult-to-cut ASTM F-1537 cobalt-chromium (CoCr) alloy. The prototype differs from the already existing indirect cooling systems by using a modified cutting insert that allows a larger volume of cryogenic fluid to flow under the cutting zone. For designing the prototype analytical

Robot geometrical calibration aims at reducing the global positioning accuracy of a robotic arm by correcting the theoretical values of the kinematic parameters. A novel method for the geometrical calibration of robotic arms used in industrial applications is proposed. The proposed approach mainly focuses on the final positional accuracy of the robotic tool center point (TCP) when executing an industrial

In automatic non-destructive testing (NDT), weld bead tracking is usually performed outside. However, irregular weld boundaries, unconstrained illumination, and rough metal surfaces can cause noise, which increases the difficulty of seam tracking. In this paper, a method of parallel structured light (PSL) sensing based on deep learning and information fusion is proposed to detect weld lines. First

Finite element analysis is commonly used to investigate the thermal-mechanical phenomena during welding. To improve the computing efficiency of finite element analysis for welding thermal conduction, a novel Newton–Raphson method (NRM) without the computation of inverse matrix and a hybrid method combing the NRM and conventional implicit method (IMP) were developed. Comparison of computing time between

Micro-milling through mechanical chip removal process has attracted much attention among researchers due to its flexibility and productivity that allow an extensive application for manufacturing several types of micro-components for the modern-day world. Its potential is continuously growing as the market demands continuous innovation in the manufacturing of high precision products with progressively

Nowadays, a challenging scenario involving additive manufacturing (AM), or 3D printing, relates to concerns on the manufacturing of electronic devices. In particular, the possibility of using fused filament fabrication (FFF) technology, which is well known for being very widespread and inexpensive, to fabricate structures with embedded sensing elements, is really appealing. Several researchers in this

Nowadays, the adhesive bonding method has a very strong presence in the most varied industries, especially in aeronautics, which strongly boosted the use of adhesively bonded joints. Curved bonded joints are commonly used in the aeronautical industry, where curved panels typically made of carbon fibre-reinforced polymer (CFRP) are joined to fabricate several fuselage parts. This work compares the performance

Variation propagation models play an important role in part quality prediction, variation source identification, and variation compensation in multistage manufacturing processes. These models often use homogenous transformation matrix, differential motion vector, and/or Jacobian matrix to represent and transform the part, tool and fixture coordinate systems and associated variations. However, the models

Cavitation-induced erosion plays an important role in the material removal process of ultrasonic-assisted fluid jet machining. The influence of the ultrasonic and hydrodynamic parameters on the cavitation features was investigated in the present study. A numerical method was used to model the cavitation involved in the fluid jet flow field under the ultrasonic vibration condition. Experiments were

Selective laser melting (SLM) has emerged as one of the leading additive manufacturing (AM) processes for the fabrication of complex metallic components, due to its capability to achieve high quality at acceptable times. However, due to the complexity of physical phenomena occurring during SLM, such as heat transfer and phase transformations, laser absorption, molten metal flow, and moving interfaces

When reporting surface quality, the roughest surface is a reference for the measurements. In LPBF due to recoil pressure and scan movement, asymmetric surface is shaped, and surface roughness has different values in different measurement orientations. In this research, the influence of the laser powder bed fusion (LPBF) process parameters on surface tension and roughness of Ti-6AI-4 V parts in three

This article has been retracted. Please see the Retraction Notice for more detail: https://doi.org/10.1007/s00170-020-06269-8

The cooling system is a critical element in tooling for hot stamping high-strength aluminium alloys, for which very high quenching rates are required to ensure a supersaturated solid solution state in formed parts. To enhance cooling, ducts within the tools should be close and conformal to the surface die profile. Currently, ducts with curved profiles are made by drilling short straight lengths in

Customized mechanical products based on orders have characteristics such as small batch sizes and multi-variety in production, which results in less availability of sample data related to assembly. Therefore, a problem of prediction of assembly precision exists due to the small number of samples. This paper studies the prediction method of mechanical product assembly precision based on the fusion of

A Ni-Cr-B-Si-Fe-based filler alloy powder has been synthesized by mechanical alloying technique in a high-energy ball mill to join Inconel 718 (IN 718) by transient liquid phase (TLP) bonding. The structural analysis of the synthesized alloy powders was done by field emission scanning electron microscope (FESEM), X-ray diffraction (XRD), field emission transmission electron microscope (FETEM), and

This note addresses the transient behavior of the different point-to-point motion control strategies. The transition between the high-speed velocity control and the high-precision position feedback often leads to undesirable overshoot and residual oscillation. This study first introduces the use of an integrated H∞-chain scattering description (CSD) synthesized controller for a unified point-to-point

Cutting edge micro-geometry plays an important role in machining operations. An appropriate shape and size of the cutting edges improve wear resistance, tool life, and process reliability. This study presents an experimental exploration to understand the rounded cutting edge of solid carbide end mills with CrTiAlN coating on milling SUS-316L steel, and the tool performance in terms of cutting force

The cylindricity and coaxiality of the stepped shaft are important parameters reflecting the vibration characteristics of the rotating machines system. In order to evaluate the cylindricity and coaxiality of the stepped shaft accurately, the paper proposes a cylindrical profile measurement model, which takes into account five kinds of systematic errors and analyzes the combined effects of five systematic

Due to its exceptional electrical, optical, chemical and magnetic properties, tin oxide (SnO and SnO2), which is a functional material, has gained enormous attention for use in a variety of applications. Films of SnOX have a direct band gap between the ranges of 2.2 and 3.6 eV, with these films finding usefulness in various functions such as solar cells, transparent conducting oxides for gas sensors

Titanium alloy, with superior mechanical properties, is widely used to manufacture key parts in the aerospace industry. Nonetheless, there exist some problems in machining titanium alloy, such as low machining efficiency, serious tool wear, and difficulty to guarantee the surface quality. In this paper, the comparative experimental study is conducted on milling the titanium alloy TC11 with indexable

This paper presents a novel method to identify the squareness errors of computer numerical control (CNC) machine tools based on double ball bar (DBB) measurements. A series of spherical S-shaped paths are proposed to measure the squareness errors, instead of the generally used circular detection paths since the presented method requires only one experimental setup, and three translation axes are linked

The machinability of 7055 aluminum alloy with wide temperature range is examined, with focus on the three cutting forces, surface quality and work hardening of the material under low, medium, and high temperatures. The results demonstrate that, under low temperature, the work hardening depth of 7055 aluminum alloy is almost insensitive to the cutting speed, whereas at a higher cutting speed, the work

To predict the residual stress distribution of the Ti-4Al-1.5Mn (TC2) alloy in the manufacturing process, quickly and accurately, a precise dynamic constitutive model for rheological behavior and a new simplified approach for numerical simulation were proposed. The dynamic stress-strain curves indicate that the enhancement effect and plasticizing of the TC2 alloy are sensitive to high strain rates

Advanced high-strength steels (AHSS) despite excellent properties with low weight and high strength have the concern of high springback occurrence. The amount of springback can be reduced by hot forming process. In this paper, the influence of temperature rises on the springback quantities generated potentially during a hot stamping process of the DP780 steel is investigated. To obtain a proper description

Ultra-precision single-point diamond turning (SPDT) is a recent realm in advanced manufacturing of optical components with nanometric features. SPDT has various applications in different industry sectors including space science, biomedical engineering, military, defense, and optics. However, different factors negatively impact the outcome of SPDT process and limit the success of optical surface generation

In this paper, an autonomous seam recognition and feature extraction method for multi-pass welding based on laser stripe edge guidance network is proposed to overcome the interference of strong reflection, spatter, and arc noise in actual welding environment. Firstly, the laser stripe edge guidance network consisting of modified VGGnet, progressive laser stripe feature extraction, non-local laser stripe

Critical interference error can be mostly resulted from illogical tool-path generations in the penetration and retraction segments of internal cylindrical thread helical milling. Therefore, a less interference tool-path planning method is proposed for the quarter revolution penetration and retraction trajectories in internal cylindrical thread helical milling. Firstly, the parametric expression of

The original published article contained a mistake.

The aero-engine blades are mostly thin-walled with complex structures, which are prone to flutter, deformation during processing. All these characteristics make it difficult to machine the blade qualified. In order to improve the precision and efficiency of blades machining, a self-adaptive clamp machining process method is proposed in this paper. Then a self-adaptive auxiliary fixture of low-melting-point

Controlling and dosing electrolytes is a key challenge in the operation of electroplating process chains. Electrolyte components are continuously degraded and dragged out during the production process. This process is influenced by a variety of internal and external factors such as process parameters, the electrolyte itself, anodes, the substrates and the production environment. The exact analytical

In this study, the vibration transmitted solely from a spindle to the worktable is proposed to be a crucial feature of wear prediction models for machine tools. To validate the effectiveness of the proposed feature, a feature ranking and screening methodology was also used for developing a tool wear prediction model. First, the features extracted from vibration signals were ranked according to their

Recent technological advances in computer vision and the advent of commercial RGB-D sensors have certainly boosted 3D modeling applications. This work presents an integrated system that enables the digitization of big objects, like vehicles, with low-cost RGB-D sensors. The implemented system can be used for visualization and monitoring of vehicles in large fleets that currently require a time-consuming

The quality of the workpiece produced by CNC machine tool is primarily due to the degree of precision and stability of the machines themselves. In general, the quality measures the degree of conformity of a part with predefined dimensions and geometric specifications. However, a simple measure does not identify the contribution of each source of error affecting the room. It is therefore important to

Local heat clamp bending equipment for carbon fiber-reinforced thermoplastic (CFRTP) sheets has been developed. The equipment holds a CFRTP sheet with thin metal foils to heat the bending region to the resign melting temperature and then bends the sheet keeping the hold by the foils under continuous pressure application during cooling. Using this equipment, it has been revealed that even a unidirectional