Spiral Chip Research Articles

Analysis of tool wear of TiAlN coated tool, machined surface morphology and chip during titanium alloy milling

TiAlN coated tools, known for their excellent resistance to high-temperature and low friction coefficient, are widely used in the processing Ti-6Al-4 V alloy. This study conducted a systematic analysis of the wear phenomenon of TiAlN coated tools during the dry milling of Ti-6Al-4 V alloy. Based on molecular dynamics (MD) and experiments, the interaction mechanism between diffusion wear and other wear mechanisms was investigated. The study further investigated the influence of tool wear on the machined surface morphology and chips. The results revealed tool diffusion wear was identified as the outward diffusion of Co and W elements. Ti element diffusion was more responsive to changes in temperature and pressure. During the tool wear process, a synergistic effect was observed between diffusion wear and adhesion wear. The combined impact of diffusion wear and oxidation wear weakened the tool's strength. The main forms of defects on the machined surface were grooves, pits, surface tears, and adhesion. As tool wear increased, the aggravation of grooves was the main reason for the reduction of roughness of machined surface. Additionally, as tool wear increased, the chip transitioned from a conical spiral chip to an arc-shaped chip, and an increase in the sawtooth degree of chips.

Performance Improvement of Flow Rate of Spiral Chip Feeder in Domestic Cattle Manure monitor Making Machine

The abstract outlines a study focused on the stability and effectiveness of a screw feeding mechanism designed for the outlet of pulping material in a screw reactor. This reactor functions as a continuous system where material is transported and mixed by a screw (augur). The study emphasizes the importance of operational conditions in influencing the process outcomes. To efficiently understand and optimize the system, the researchers employed modelling techniques, which are often quicker and more cost-effective than conducting experiments. The paper provides a comprehensive list of modelling approaches, both validated by experiments and theoretical, that is applicable to various aspects of screw reactor operation. Additionally, the study delves into new product development, specifically shaping a conical screw feeding reactor along with its shaft and flights design. A crucial aspect analyzed is the radial force effect on the flight surface during spiral rotation. Structural engineering techniques were employed to ensure the sustainability of the design, with validation results confirming its effectiveness. Keywords: Screw, Radial Force, Pulping Material

Energy and Security-Aware Data Transmission in IoT: An Optimal Cluster Head Selection Approach with Spiral Chip Dynamics Optimizer (SCDO)

Energy and Security-Aware Data Transmission in IoT: An Optimal Cluster Head Selection Approach with Spiral Chip Dynamics Optimizer (SCDO)

Inertia-magnetic microfluidics for rapid and high-purity separation of malignant tumor cells

The existence of many background cells and the size overlap between white blood cells (WBCs) and malignant tumor cells (MTCs) pose a challenge for the efficient separation of MTCs from effusions or bloods. Herein, we proposed an inertia-magnetic cell separation (IMCS) device integrating a trapezoidal spiral chip with an immunomagnetic chip for high-throughput, high-recovery, and high-purity separation of MTCs from malignant pleural and peritoneal effusions (MPPEs). First, the effects of flow rate and particle size on separation performances in two separate chips were investigated. Then, the performances of the integrated IMCS device were characterized using blood samples spiked with three different tumor cells (A549, MCF-7, and MDA-MB-231 cells). The results showed that all the three tumor cells were separated from the WBCs with a high-throughput of ∼ 3200 μL/min, a high-recovery ratio of > 90%, and a high-purity of > 70%. Finally, we successfully separated MTCs from four clinical MPPE samples with an average purity of > 70%. As compared with conventional microfluidic devices using single technologies, our IMCS device combines the advantages of both passive size-dependent separation technology and immunomagnetic separation technology and can accurately separate tumor cells from WBCs of comparable sizes at a high throughput. Therefore, we envision that the high-purity MTC separation ability of our IMCS device can improve the sensitivity and efficiency of cytological examination.

A microfluidic device for enhanced capture and high activity release of heterogeneous CTCs from whole blood

Circulating tumor cells (CTCs) are tumor cells that spontaneously detach from the primary focus, and early detection and characterization of CTCs is vital for cancer diagnosis and appropriate treatment. Current methods commonly use EpCAM to capture CTCs, but this results in a loss of information on other CTC subsets (EpCAM-negative cells) due to the heterogeneity of CTCs. Here, we report a novel microfluidic device that integrates the capture and release of heterogeneous CTCs directly from whole blood. A spiral chip was designed for the separation of differently sized cells, and larger CTCs were effectively separated from smaller blood cells with a 98% recovery rate. CD146-containing magnetic beads were used to complement the EpCAM-based CTC capture methods, and the capture efficiency of Fe3O4@Gelatin@CD146/EpCAM increased by 20% over Fe3O4@Gelatin@EpCAM. Finally, MMP-9 was employed to release CTCs with high efficiency and less damage by degrading gelatins on the surface of Fe3O4. The established method was successfully applied to CTC capture and release in a simulated patient's whole blood. The developed method achieved enhanced capture and high activity release of heterogeneous CTCs with less interference by blood cells, which contributes to the early detection and clinical downstream analysis of CTCs.

A spiral microfluidic chip endows high efficiency single cell alignment at extremely low flow for ICP-MS analysis

A spiral microfluidic chip integrating periodic micro pillars was designed to achieve focusing and sorting of cells at ultra-low flow rate. It enables high efficiency single cell analysis by combining with time resolved inductively coupled plasma mass spectrometry (TRA-ICP-MS). The spiral chip facilitates focusing of particles or cells through the action of secondary flow and inertial induced lift force. The simulation illustrated that the periodic micro-pillars enhanced the influence of secondary flow and resulted in a superb focusing of cells. The focusing capability of the chip was demonstrated by using fluorescent particles of 9.77 μm in diameter and MCF-7 cells stained with DiI, wherein excellent focusing/alignment was achieved at flow rates of as low as 5 μL min−1 for fluorescent particles and 10 μL min−1 for MCF-7 cells, respectively. Furthermore, the spiral microfluidic chip was used for focusing/alignment of MCF-7 and LoVo cells after incubating with anticancer metal prodrug (cobalt curcumin complex [Co(tpa)(cur)](ClO4)2). The uptake of this prodrug in individual MCF-7 and LoVo cell was investigated with detection by TRA-ICP-MS in single cell resolution. The two types of cancer cells exhibit different uptake behaviors of the complex, and differences among individual cells of each type were also identified. A single cell detection efficiency of 67.5 ± 4.6% was obtained at the flow rate of 50 μL min−1.

Development of fixed abrasive grain tool with continuous spiral chip pocket

Development of fixed abrasive grain tool with continuous spiral chip pocket

Experimental study on deep hole drilling of GH4169 alloy

GH4169 alloy material has good corrosion resistance, radiation resistance and other excellent properties, and has been widely used in aerospace and other manufacturing fields. At the same time, due to its severe machining hardening phenomenon and high cutting force during machining, it is also one of the typical difficult-to-machine materials, and the deep hole drilling of GH4169 alloy has been rarely studied. In this paper, the deep hole drilling test of GH4169 is studied, and BTA system is adopted in the test, the wear and failure modes of the cutting tool, and the change of chip morphology were analyzed. Results showed that the middle cutter tooth wear focused on central blade, the wear of the center tooth occurs mainly at the tip of the cutter tooth, the wear of edge tooth mainly occurs at the arc of the tool tip where the main cutting edge is connected with the secondary cutting edge: the chips produced by the central cutter tooth are mostly short and small c-shaped chips, the chip produced by the middle tooth is not easy to break the chip, most of which are elongated spiral chip, the cuttings produced by the edge tooth are not easy to discharge, and most of them are hard spiral coils.

Effects of machining surface and laser beam scanning strategy on machinability of selective laser melted Ti6Al4V alloy in milling

Overlapping melting trajectories and partially-melted powders result in poor surface morphology and high surface roughness values (Ra = ~13.34 μm) of selective laser melted (SLMed) Ti6Al4V alloy. Secondary processing of SLMed components is thus an essential finishing operation to produce functional SLMed parts in precision engineering. This paper investigates the effects of laser scanning strategies (0°, 67.5° and 90° laser scanning schemes) and machining surfaces (top and front surfaces) on the machining performance of SLMed Ti6Al4V alloy in milling, compared with that of annealed ASTM B265 Ti6Al4V alloy. High degree of anisotropy of SLMed Ti6Al4V alloy is reflected in cutting force, surface morphology and surface roughness on different machining surfaces. The machining anisotropy is dominated by the anisotropy of microstructure and mechanical properties of SLMed Ti6Al4V alloy, where the anisotropy weakens following the sequence of 0°, 90° and 67.5° SLMed samples. It is verified that high cutting speed can improve machining anisotropy features of SLMed titanium alloy. The chip shape of SLMed Ti6Al4V alloy is a typical conical spiral chip, and the bending degree and length of chips produced by SLMed Ti6Al4V alloy are larger than those produced by annealed Ti6Al4V alloy.

Culture of circulating tumour cells derived from non-small cell lung cancer.

e21692 Background: Tumour tissue-based information is limited. Liquid biopsy can provide valuable real-time information through circulating tumour cells (CTCs). Profiling and expanding CTCs may provide avenues to study transient metastatic disease. Methods: 70 NSCLC patients were recruited. CTCs were enriched using the spiral microfluidic chip and a RosetteSep™ using bloods from NSCLC patients. CTC cultures were carried out using the Clevers media under hypoxic conditions. CTCs were characterized using immunofluorescence and mutation-specific antibodies for samples with known mutation profiles. Exome sequencing was used to characterized CTC cultures. Results: CTCs ( > 2 cells) were detected in 38/70 (54.3%) of patients ranging from 0-385 CTCs per 7.5ml blood. In 4/5 patients where primary tumours harboured an EGFR exon 19 deletion, this EGFR mutation was also captured in CTCs. ALK translocation was confirmed on CTCs from a patient harbouring an ALK-rearrangement in the primary tumour. Short term CTC cultures were successfully generated in 9/70 NSCLC patients. Whole exome sequencing confirmed the presence of somatic mutations in the CTC cultures with mutational signatures consistent with NSCLC. Conclusions: This study demonstrates a workflow for ex vivo culture of CTCs from NSCLC blood samples.

The chips generated during up-milling and down-milling of pine wood by helical router bits

Machining aspects with helical edge router bits (helix angle 15°, 30°, 45°, and 60°) with a cutting circle diameter of 8 mm were studied. The purpose of the research work was to investigate chip formation and surface roughness characteristics in milling pine wood by the straight and helical edge bits. The chips generated could be classified into four types by sieving into spiral chip (5 mesh), flow chip (10 mesh), thin chip (30 mesh), and granule chip (< 30 mesh). The experimental results show that spiral chips were generated most often (on a weight percentage basis) by the bits during down-milling process. More flow and thin chips were produced by the bits during up-milling process. Better surface roughness was produced by bits during down-milling compared to up-milling. With increasing helix angle of the bits, the amount of spiral and flow chips increased and granule chips were reduced. The machined surface produced was better in roughness (lower Ra values) as the helix angle of the bits increased both in up-milling and down-milling processes.

High-throughput sorting of eggs for synchronization of C. elegans in a microfluidic spiral chip.

In this study, we report the use of a high-throughput microfluidic spiral chip to screen out eggs from a mixed age nematode population, which can subsequently be cultured to a desired developmental stage. For the sorting of a mixture containing three different developmental stages, eggs, L1 and L4, we utilized a microfluidic spiral chip with a trapezoidal channel to obtain a sorting efficiency of above 97% and a sample purity (SP) of above 80% for eggs at different flow rates up to 10 mL min-1. The result demonstrated a cost-effective, simple, and highly efficient method for synchronizing C. elegans at a high throughput (∼4200 organisms per min at 6 mL min-1), while eliminating challenges such as clogging and non-reusability of membrane-based filtration. Due to its simplicity, our method can be easily adopted in the C. elegans research community.

A novel mechanism for user-friendly and self-activated microdroplet generation capable of programmable control.

Unlike conventional approaches that require bulky and expensive pumping equipment, herein, we present a simple method for self-activated microdroplet generation and transport inside a long microchannel. The high gas-pressure in the syringes is used to provide the built-in power of self-priming so that the continuous phase and the dispersed phase are sequentially automated into the generator junction to produce stabilized droplets. The volume ratio between the aqueous and oil phases can be adjusted in a flexible way by accurately controlling the volume of the compressed air in the two syringes, and a novel self-activated micropumping mechanism is introduced to explain this phenomenon. Through the flow rate test inside the microchannels under different conditions, it is found that the flow rate of microdroplets inside the Teflon microchannel is highly stable. As a proof of concept, this novel micropump is applied for a 3D spiral chip for flow through PCR. It is demonstrated that this self-activated micropump is acceptable for droplet-based continuous flow microfluidic PCR with the thermal-cycle controlled by a single thermostatic heater, while the real-time (RT) fluorescence signal is comparable to a commercial qPCR cycler. This self-activated, portable, and controllable droplet generator would extend the droplet-based applications to in-field analysis and facilitate the exploitation of droplet microfluidics by non-technical users.

Investigation on performance characteristics and metallographic transformation on drilling aluminium/titanium sandwich

Materials sandwiches of aluminium/titanium are widely used in structural aerospace, especially in the surface coating and skeletons of aircrafts. Due to their inhomogeneous behavior and poor machinability, drilling aluminium/titanium sandwich in one-shot operation has brought great challenges to the modern manufacturing community. In this paper, a series of experiments were conducted to understand and characterize the process of drilling aluminium/titanium sandwich. Experimental results have shown that the serrated chip is not common in drilling. Only the outer edge of the spiral chip has saw teeth because of the variable cutting speed along the cutting edge. In addition, a better understanding of the phase transformation on surface and subsurface of drilled hole has been provided. Two kinds of phase transformations on the surface of drilled hole have been observed: one is the allotropic transformation from α to β phase and the other is that from β to minor phases α′ (hexagonal martensites). All these are mainly due to the interaction of mechanical force and high temperature.

Modeling and optimization of the flute profile of micro-drill

The profile of drill flute has a great influence on the drilling performance of micro-drill. It is promising to obtain a desired flute profile with a standard wheel by adjusting the wheel position parameters during the grinding process. To investigate the flute profile characteristics under different wheel position parameters and its effect on the drilling performance, this paper presents a method for modeling and optimization of the micro-drill flute considering the wheel installation angle and the offset distance from the wheel origin to the drill blank origin. Based on this model, the flute profile of micro-drill is numerically simulated by MATLAB software firstly, and then, the 3D model of micro-drill with different flute profiles is established by UG software. Finally, the micro-drilling process on 304 austenitic stainless steel is simulated by DEFORM software, and the chip morphology and the drilling force are analyzed and discussed. The results show that the wheel installation angle has an obvious effect on the flute profile and its radial rake angle and flute width, and the wheel offset distance only influences the flute width evidently. The micro-drill with flute ground by smaller wheel installation angle owns straighter cutting lip shape and larger chip evacuation capacity, and its thrust force and torque are smaller than those of other micro-drills. Moreover, spiral chip is generated due to the intense side curl and up curl of the chip, resulting in the easiness of the chip removal. However, for the micro-drills with flute ground by larger wheel installation angle, the chip morphology is string and the drilling force is larger. At last, the mathematical model of the drill flute and its numerical simulation result are validated by experimentally fabricating the micro-drill flute. Then, the optimized micro-drill is manufactured by a six-axis computer numerical control (CNC) grinding machine, and its flute profile is fabricated using a standard conical grinding wheel with a smaller wheel installation angle.

Monte Carlo Modeling-Based Digital Loop-Mediated Isothermal Amplification on a Spiral Chip for Absolute Quantification of Nucleic Acids.

Digital loop-mediated isothermal amplification (dLAMP) is an attractive approach for absolute quantification of nucleic acids with high sensitivity and selectivity. Theoretical and numerical analysis of dLAMP provides necessary guidance for the design and analysis of dLAMP devices. In this work, a mathematical model was proposed on the basis of the Monte Carlo method and the theories of Poisson statistics and chemometrics. To examine the established model, we fabricated a spiral chip with 1200 uniform and discrete reaction chambers (9.6 nL) for absolute quantification of pathogenic DNA samples by dLAMP. Under the optimized conditions, dLAMP analysis on the spiral chip realized quantification of nucleic acids spanning over 4 orders of magnitude in concentration with sensitivity as low as 8.7 × 10-2 copies/μL in 40 min. The experimental results were consistent with the proposed mathematical model, which could provide useful guideline for future development of dLAMP devices.

Performance Improvement of Flow Rate of Spiral Chip Feeder in Pulping Screw Unit

Performance Improvement of Flow Rate of Spiral Chip Feeder in Pulping Screw Unit

Microfluidic chip using foil‐assisted CO 2 laser ablation for suspended particle separation

Separation is one of the important pretreatment processes during detection in lab-on-a-chip. In this reported work, polydimethylsiloxane (PDMS) on a glass microchip with a combination of the spiral channel and backward facing step structure was designed to optimise the separation of suspended particles without any extra active powers of the electric or magnetic field. The spiral microfluidic chip was fabricated first by the foil-assisted CO2 laser ablated polymethylmethacrylate (PMMA) master mould, followed by repetitive PDMS moulding and then bonded to a glass substrate. The CO2 laser ablation of PMMA in air normally generated poor surface quality comprising bulges and scorches. The metal-foil-assisted laser ablation can effectively improve the above defects with conducting cover protection. The average height of the bulges was reduced from 5.0 to 1.5 μm and the channel width was reduced from 230 to 120 μm. The finished separation chips were operated at various syringe-controlled flow rates of 5–20 µL/min to test the performance. A high separation efficiency of about 99% could be achieved within a certain flow range of less than 15 µL/min under the simple structure with low-cost and time-saving.

The evaluation of the effects of control factors on surface roughness in the drilling of Waspaloy superalloy

In this study, the effects of cutting tool type (Ct), cutting speed (Vc), feed rate (f) and drill bit angle (A) on the average surface roughness (Ra) were investigated in the drilling of Waspaloy superalloy with coated and uncoated solid carbide drills. Experimental studies were performed in the orthogonal array of L18 (21×33) by using Taguchi method. A second order predictive equation was developed with Linear Regression Analysis and coefficient of correlation for Ra calculated as R2=96.9%. The most effective parameters on Ra were determined as A, f, Vc and Ct with 49.44%, 15.0%, 14.45% and 13.47% contribution ratios, respectively. Ra surface roughness values increased with the increasing tool wear. In this study, the chip formation and tool wear were also evaluated. Three types chip formation such as spiral chip, string chip and short chip were observed in the drilling of Waspaloy with solid carbide drills.

Effect of operating parameters on the drilling behavior of Zr57.5Cu11.2Ni13.8Al17.5 bulk metallic glass

Abstract