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Tool wear has become a critical concern in machining for various reasons including financial savings and environmental protection. However, having a good prediction of tool life is still an important request to the machining community. The work investigate the tool life in machining of AA7075/10 wt% SiC (particle size 10–20 µm), AA7075/15 wt% SiC (10–20 µm), AA7075/15 wt% SiC (10–20 µm) and AA7075/15 wt% SiC (20–40 µm) composite. Machining of AA7075/SiC composite rods was performed by carbide insert CNMG 120404, 08,12EM, grade 6615 under different machining parameters. The investigation shows the influences of machining parameters like spindle speed, depth of cut, feed rate and nose radius affecting tool life during machining operation of AA7075/SiC composites. Novelty of this research is that it support to real aspects of composite turning expertise owing to new relations about effects of SiC particle size and weight % on tool life, and relevant characterization AA7075/ SiC composites.

Experiments were conducted to investigate the cutting forces during the machining of AA7075/15 wt% SiC (20–40 µm) composite. Process parameters such as cutting speed, feed, depth of cut and nose radius were varied to assess their effects on the cutting forces (tangential force, feed force and radial force). The dry turning of AA7075/15 wt% SiC was done on computerized numerical control (CNC) machine as per design of experiments. Mathematical models for the tangential force, feed force and radial force were determined by using the response surface methodology (RSM). Accuracy of the mathematical model is verified using experimental measurements. Desirability analysis was used to optimize the turning parameters to minimize the tangential, feed and radial force. Genetic algorithms (GA) was also used to optimize the turning parameters. The optimum values of the parameters obtained from the GA, experimental result, revalidated result and desirability analysis were compared. Calculated cutting forces were in line with the experimental results. A simple and practical method was devised to calculate the cutting forces. It was found that turning at optimum parameter values obtained from the GA decreased the tangential force, feed force and radial force values by a substantial amount, as compared to turning at optimum values of cutting speed, feed, depth of cut and nose radius obtained by other approaches. Research findings will act as recommendations for choice of optimal cutting conditions to minimize fluctuation of cutting forces.

Quality of product and rate of production are affected by tool wear. Therefore, correct assessment of tool wear and its minimization is essential. Surface characteristics are affected by tool wear. AA7075/ 10 wt.% SiC (20–40 µm) composite was fabricated by stir casting process. Bars of 15 × 2.5 cm were obtained after casting. Initial machining was done on lathe machine by locally fabricated tool to remove the projections on casted bar and to bring size to 14 × 2.1 cm. Samples were also prepared for microscopic examination. Experiment were planned as per Design of Experiments (DOE) technique. Machining of AA7075/ 10 wt.% SiC composite bars was done by using carbide insert CNMG 120,404, 08,12EM, grade 6630 on CNC turning machine. The objective of this research is to study the effect of tool wear on surface roughness, during dry turning of AA7075/ 10 wt.% SiC (20–40 µm) composite. Tool wear and surface roughness were measured. Flank and Crater wear of inserts were extensively studied. Response surface methodology (RSM) was used for modeling to predict surface roughness and tool wear at different values of process parameters i.e. cutting speed, feed, depth of cut and nose radius, while turning AA7075/ 10 wt.% SiC composite. Experimental data of finish turning of AA7075/10 wt% SiC composite can be utilized by industries. Novelty of this research is that it contributes to practical features of composite machining know-how, due to discovering relations between tool wear and surface roughness, and pertinent surface roughness characterization of AA7075/ 10 wt.% SiC composite.

Power consumption has become a serious issue in current manufacturing for numerous reasons such as, financial savings and environmental protection. The correct calculation of the power consumption for various machining processes remains a challenge. This paper presents an experimental investigation of the power consumption during the turning operation of AA7075/10 wt% SiC (particle size 10–20 μm), AA7075/10 wt% SiC (particle size 20–40 μm), AA7075/15 wt% SiC (particle size 10–20 μm) and AA7075/15 wt.% SiC (particle size 20–40 μm) composite. Machining of the AA7075/ 10 wt% SiC and AA7075/ 15 wt% SiC composites bars was done by using carbide insert CNMG 120404, 08,12EM, grade 6615 at various cutting parameters. Study displays impacts of cutting parameters such as cutting speed, depth of cut, feed rate and nose radius on power consumption during the turning operation of AA7075/SiC composites. Minimum power was consumed during the turning of 04 type of AA7075/SiC composites mentioned in this research, when turning was done at cutting speed of 90 m/min, feed of 0.15 mm/rev, depth of cut of 0.20 mm and nose radius of 0.40 mm. The novelty of this research is that it contributes to the practical features of composite machining knowledge by discovering relations between the effects of SiC particle size and weight percentage on the power consumption, and pertinent power consumption characterisation AA7075/ SiC composites.

Fixed duration multidrug therapy (FDT–12 months) is recommended by the WHO for multibacillary (MB) Hansen's disease (HD). However, highly bacillated patients tend to experience problems such as painful neuritis, worsening nerve function, delayed regression of lesions, and relapses. There is also concern about the increasing rate of relapse and antimicrobial resistance. Persistent or slowly regressing skin lesions and disabilities can occur even after completion of treatment. The decline in expertise to diagnose and treat Hansen's disease and poor treatment adherence are additional challenges. It is suggested that prolonging antimicrobial therapy, adding immunotherapy, increasing the dosage of rifampicin, adding more potent bactericidal drugs, and improving diagnostic services and treatment adherence may help manage highly bacillated patients. [Extracted from the article]

This letter to the editor responds to a study on the laboratory detection of bacterial pathogens and the clinical and laboratory response of syndromic management in patients with cervical discharge. The authors express concerns about the study's methodology and results, particularly regarding the identification of ureaplasma as the cause of cervicitis based solely on isolation. They argue that ureaplasma may be a commensal organism rather than a pathogen, and that its presence does not necessarily indicate infection. The authors also highlight the lack of a control group and suggest that further research is needed to better understand the role of ureaplasma in cervicitis. [Extracted from the article]