Seizure Resistance Research Articles

Dietary fiber content in clinical ketogenic diets modifies the gut microbiome and seizure resistance in mice

The gut microbiome modulates the anti-seizure effects of the ketogenic diet, but how specific dietary formulations differentially modify the gut microbiome in ways that impact seizure outcome is poorly understood. We find that medical ketogenic infant formulas vary in macronutrient ratio, fat source, and fiber content and differentially promote resistance to 6-Hz seizures in mice. Dietary fiber, rather than fat ratio or source, drives substantial metagenomic shifts in a model human infant microbial community. Addition of fiber to a fiber-deficient ketogenic formula restores seizure resistance, and supplementing protective formulas with excess fiber potentiates seizure resistance. By screening 13 fiber sources and types, we identify metagenomic responses in the model community that correspond with increased seizure resistance. Supplementing with seizure-protective fibers enriches microbial genes related to queuosine biosynthesis and preQ0 biosynthesis and decreases genes related to sucrose degradation and TCA cycle, which are also seen in seizure-protected mice that are fed fiber-containing ketogenic formulas. This study reveals that different formulations of ketogenic diets, and dietary fiber content in particular, differentially impact seizure outcome in mice, likely by modifying the gut microbiome. Understanding interactions between diet, microbiome, and host susceptibility to seizures could inform novel microbiome-guided approaches to treat refractory epilepsy.

Refining management strategies for Lennox-Gastaut syndrome: Updated algorithms and practical approaches.

Lennox-Gastaut syndrome (LGS) is a severe developmental and epileptic encephalopathy (DEE) characterized by multiple types of drug-resistant seizures (which must include tonic seizures) with classical onset before 8 years (although some cases with later onset have also been described), abnormal electroencephalographic features, and cognitive and behavioral impairments. Management and treatment of LGS are challenging, due to associated comorbidities and the treatment resistance of seizures. A panel of five epileptologists reconvened to provide updated guidance and treatment algorithms for LGS, incorporating recent advancements in antiseizure medications (ASMs) and understanding of DEEs. The resulting consensus document is based on current evidence from clinical trials and clinical practice and the panel's expert opinion, focusing on new ASMs with novel mechanisms of action, such as highly purified cannabidiol and fenfluramine. For a patient presenting with newly diagnosed LGS or suspected LGS, the recommended first-line treatment continues to be valproate. If this is ineffective as monotherapy, adjunctive therapy with, firstly, lamotrigine and secondly, rufinamide, is recommended. If seizure control remains suboptimal, subsequent adjunctive ASM treatment options include (alphabetically) cannabidiol, clobazam, felbamate, fenfluramine, and topiramate, although evidence for these is more limited. Whenever possible, no more than two ASMs should be used together. Nonpharmacological treatment approaches should be used in conjunction with ASM therapy and include ketogenic diet therapies, vagus nerve stimulation, and corpus callosotomy. Patients with LGS that has evolved from another type of epilepsy who are not already being treated with valproate should be transitioned to valproate and then managed using the same algorithm as for newly diagnosed LGS. Older patients with established LGS should be reviewed at least annually by a suitably experienced neurologist. The revised guidance aims to improve seizure control and quality of life for patients with LGS through personalized, evidence-based treatment strategies while addressing the challenges of accurate diagnosis and management in a rapidly evolving therapeutic landscape. PLAIN LANGUAGE SUMMARY: Lennox-Gastaut syndrome (LGS) is a severe type of epilepsy that usually starts in childhood but continues into adulthood. It is characterized by a variety of different types of seizures (abnormal electrical activity in the brain), which are difficult to treat and often cause people with the condition to fall and injure themselves. Most people with LGS have learning difficulties and need a lot of support, often in residential care. The authors are experts in treating people with LGS and this article provides up-to-date guidance and advice on how best to care for those with the condition.

Effect of peening with fine iron-sulfide particles on the rotating bending fatigue properties of low alloy steel and formation of iron-sulfide layer

Low alloy steels were subjected to peening with fine iron sulfide particles (FeS-peening) under ambient conditions to transfer a layer of such particles, which can improve seizure resistance and sliding properties, and thus enhance the fatigue characteristics of the steel. This process was performed without the use of aqueous Na2S2O3 and the specimens were assessed using electron probe microanalysis and rotating bending fatigue tests. Treated specimens exhibited higher fatigue limits as a result of high degree of compressive residual stress generated on the steel surface. The effects of residual stress on the fatigue limit were quantitatively investigated using a modified Goodman diagram. Sample cross-sections were observed using electron backscattered diffraction, which confirmed that FeS-peening formed fine surface grains. Grain refinement was determined to be at least partly responsible for the improved fatigue properties of the steel following FeS-peening.

Dietary fiber content in clinical ketogenic diets modifies the gut microbiome and seizure resistance in mice.

The gut microbiome is emerging as an important modulator of the anti-seizure effects of the classic ketogenic diet. However, many variations of the ketogenic diet are used clinically to treat refractory epilepsy, and how different dietary formulations differentially modify the gut microbiome in ways that impact seizure outcome is poorly understood. We find that clinically prescribed ketogenic infant formulas vary in macronutrient ratio, fat source, and fiber content and also in their ability to promote resistance to 6-Hz psychomotor seizures in mice. By screening specific dietary variables for their effects on a model human infant microbial community, we observe that dietary fiber, rather than fat ratio or source, drives substantial metagenomic shifts. Addition of dietary fiber to a fiber-deficient ketogenic formula restores seizure resistance, and supplementing protective ketogenic formulas with excess dietary fiber further potentiates seizure resistance. By screening 13 fiber sources and types, we identify distinct subsets of metagenomic responses in the model human infant microbial community that correspond with increased seizure resistance in mice. In particular, supplementation with seizure-protective fibers enriches microbial representation of genes related to queuosine biosynthesis and preQ0 biosynthesis and decreases representation of microbial genes related to sucrose degradation, which is also seen in seizure-protected mice that are fed fiber-containing ketogenic infant formulas. Overall, this study reveals that different formulations of clinical ketogenic diets, and dietary fiber content in particular, differentially impact seizure outcome in mice, likely through modification of the gut microbiome. Understanding interactions between dietary components of the ketogenic diet, the gut microbiome, and host susceptibility to seizures could inform novel microbiome-guided approaches to treat refractory epilepsy.

Molybdenum Disilicide (MoSi2) and Ferrophosphorus Particles (FemPn) Improve the Anti-Seizure Properties of Copper-Tin-Bismuth Composites under Conformal and Nonconformal Contacts

Seizure is a severe accident that can abruptly stop or even damage running equipment. Improving the anti-seizure properties of friction pair materials is also crucial as lubricating and wear resistance. While the tribological performances of molybdenum disilicide (MoSi2) and ferrophosphorus (FemPn) particle-doped copper-tin-bismuth (Cu-Sn-Bi) composites have been investigated in previous studies, the specific effects of MoSi2 and FemPn particles on the anti-seizure property of Cu-Sn-Bi materials remain unclear. This study explores the seizure resistance of Cu-Sn-Bi composites containing MoSi2 and/or FemPn under conformal and nonconformal contact conditions. The materials were prepared using powder sintering technology, and the metallographic structures of four types of self-lubricating copper composites were observed. Seizure resistance under starved lubrication conditions was investigated, and the worn surfaces under different contact types were discussed and analyzed. The results indicate that the addition of MoSi2 and/or FemPn particles effectively refines the grain size, and these particles exhibit different distribution trends after powder sintering. The MoSi2 and FemPn particles improved the maximum seizure load of copper-based composite samples by 66.67% and 84.62%, respectively. The seizure forms under different contact types were also discussed.

Dietary Fibers in Clinical Ketogenic Diets Promotes Seizure Resistance in Mice Through Modulation of Gut Microbiome

Dietary Fibers in Clinical Ketogenic Diets Promotes Seizure Resistance in Mice Through Modulation of Gut Microbiome

Carvedilol increases seizure resistance in a mouse model of SCN8A-derived epilepsy.

Patients with mutations that alter the function of the sodium channel SCN8A present with a range of clinical features, including mild to severe seizures, developmental delay, intellectual disability, autism, feeding dysfunction, motor impairment, and hypotonia. In an effort to identify compounds that could be potentially beneficial in SCN8A-associated epilepsy, Atkin et al. conducted an in vitro screen which resulted in the identification of 90 compounds that effectively reduced sodium influx into the cells expressing the human SCN8A R1872Q mutation. The top compounds that emerged from this screen included amitriptyline, carvedilol, and nilvadipine. In the current study, we evaluated the ability of these three compounds to increase resistance to 6Hz or pentylenetetrazole (PTZ)-induced seizures in wild-type CF1 mice and in a mouse line expressing the human SCN8A R1620L mutation. We also evaluated the effects of fenfluramine administration, which was recently associated with a 60%-90% decrease in seizure frequency in three patients with SCN8A-associated epilepsy. While amitriptyline, carvedilol, and fenfluramine provided robust protection against induced seizures in CF1 mice, only carvedilol was able to significantly increase resistance to 6Hz- and PTZ-induced seizures in RL/+ mutants. These results provide support for further evaluation of carvedilol as a potential treatment for patients with SCN8A mutations.

Ketogenic diet therapy for pediatric epilepsy is associated with alterations in the human gut microbiome that confer seizure resistance in mice

The gut microbiome modulates seizure susceptibility and the anti-seizure effects of the ketogenic diet (KD) in animal models, but whether these relationships translate to KD therapies for human epilepsy is unclear. We find that the clinical KD alters gut microbial function in children with refractory epilepsy. Colonizing mice with KD-associated microbes promotes seizure resistance relative to matched pre-treatment controls. Select metagenomic and metabolomic features, including those related to anaplerosis, fatty acid β-oxidation, and amino acid metabolism, are seen with human KD therapy and preserved upon microbiome transfer to mice. Mice colonized with KD-associated gut microbes exhibit altered hippocampal transcriptomes, including pathways related to ATP synthesis, glutathione metabolism, and oxidative phosphorylation, and are linked to susceptibility genes identified in human epilepsy. Our findings reveal key microbial functions that are altered by KD therapies for pediatric epilepsy and linked to microbiome-induced alterations in brain gene expression and seizure protection in mice.

The Effect of the Age at Seizure Onset on Seizure Resistance in Tuberosclerosis Patients

Objective: To evaluate the clinical status of epilepsy, which is extremely widespread in tuberosclerosis patients and the findings and characteristics of a paediatric case series. Methods: The study included paediatric patients diagnosed with tuberosclerosis from clinical or genetic examination who were followed up between 2015 and 2022 in the Paediatric Neurology and Paediatric Genetics Clinics of Necmettin Erbakan University Meram Medical Faculty Hospital. A retrospective examination was made of the clinical characteristics of the patients, the electroencepahalography (EEG) reports, and radiological findings (magnetic resonance imaging [MRI], ultrasonography, echocardiography). The patients were separated into two groups of monotherapy and polytherapy according to the number of drugs used, and the groups were compared in respect of the time of onset of epilepsy. The patients were also categorised according to the presence of cortical tuber and subependymal nodule and these groups were compared in respect of the presence of epilepsy. Results: The 27 patients comprised 18 (66.6%) males and 9 (33.4%) females. Complaints on presentation were seizure and skin patches in 25 (92.5%) cases and only skin patches in 2 (7.5%). The most common finding determined on MRI was the combination of subependymal nodule and cortical tuber (51.8%). Autism spectrum disorder was present in 5 (18.5%) patients and mental retardation in 16 (59%). The age at onset of epilepsy was earlier in the polytherapy group [5±4.75 (1-18) months] than in the monotherapy group [8.0±16 (4-36) months] (p=0.032). The rates of presence of cortical tuber and subependymal nodule were similar in respect of the time of onset of epilepsy (p>0.05). Conclusion: The early onset of epilepsy in tubersclerosis patients indicates that it may have a resistant course and there may be a need for polytherapy. There may also be accompanying neuropsychiatric retardation in these patients. The clinical status of epilepsy in tuberosclerosis was found to be similar in the cortical tuber and subependymal nodule groups.

Wear and frictional attributes of Al-alloy hybrid composite dispersed with hard-ceramic (ZrO2) and solid-lubricant (Gr) particles

The objective of this study was to investigate the effects of adding two different types of reinforcing particles, hard-ceramic zirconia (ZrO2p: 0, 2, and 4 wt.%) and solid-lubricant graphite (Grp: 0, and 3 wt.%), on the sliding wear and frictional properties of stir-squeeze cast aluminum composites. For this purpose, wear tests were performed using a pin-on-disk wear tester, with emphasis on parameters such as wear rate, seizure resistance, temperature, coefficient of friction, and wear coefficient at varying sliding distances (0-5000 m at an interval of 1000 m) and under different applied pressures (0.5-2.0 MPa). Microstructural analysis showed that the particles were evenly dispersed in the aluminum matrix alloy. The addition of either particles or a combination of both reduced the wear rate significantly compared to the monolithic alloy. The seizure resistance and temperature rise were also improved, from 1.5 MPa to 2.0 MPa and 78 °C to 123 °C, respectively, with the addition of 4% ZrO2 and 3% Gr particles to the aluminum matrix alloy. The friction coefficient increased with the addition of reinforcing particles and was more noteworthy at higher pressures. The wear mechanism observed during wear surface and subsurface analysis was the creation and disintegration of a mechanically mixed layer (MML).

Chronotype and sleep disorders in children with epilepsy.

The circadian rhythm can affect the frequency and resistance of epileptic seizures. In this cross-sectional study, we examined the impact of chronobiology and sleep disturbances on children with epilepsy. One hundred and twenty-five children and adolescents (55 patients and 70 controls) were included in the study. All participants were asked to complete the Revised Child Anxiety and Depression Scale-Child Version (RCADS-CV), Sleep Disturbances Scale for Children (SDSC), Childhood Chronotype Questionnaire (CCQ). According to the CCQ results, controls had longer sleep duration (median 595 vs. 570), lower morningness-eveningness scores (median: 28 vs. 30), and higher rates of the morningness (12.9% vs. 1.8%) and intermediate (74.3% vs. 60%) chronotypes. The children and adolescents with epilepsy scored significantly higher in the Sleep breathing disorders (p = .001), Disorders of arousal nightmares (p = .044), Sleep-wake transition disorders (p = .037), Disorders of excessive somnolence (p = .001), and total SDCS (p = .046) scores. According to the RCADS-CV results, the children with epilepsy scored significantly higher in all subscales in comparison to controls (p < .05). Children and adolescents with epilepsy had shorter sleep duration were more likely to be evening-oriented and had more significant sleep disturbance symptoms compared to controls.

Improvement of Seizure Resistance in Ironing of Aluminum Alloy Sheets and Stainless Steel Cups by Utilizing Laser Textured Die Having Lubricant Pockets

Seizure during ironing negatively affects the quality of parts and die life. To prevent seizures, lubrication has to be improved. In this study, laser-textured dies with lubricant pockets were utilized to improve seizure resistance in the ironing of aluminum alloy sheets and stainless steel cups. The effects of array patterns of micro-pockets, such as grid and crossing array patterns with circular pockets, as well as a grooved array patterns on seizure resistance, were experimentally examined by strip ironing. The sheet and die materials were the A1050-O aluminum alloy and JIS SKD11 tool steel, respectively. Moreover, the underlying physics of the lubricant flow influencing the load-carrying capacity were investigated using three-dimensional computational fluid dynamics simulations. The optimum array patterns of the micro-pockets were then utilized on a tungsten carbide-cobalt (WC-Co) die surface for ironing SUS430 stainless steel cylindrical cups. The strip ironing results showed that the grid array pattern was successful in ironing sheets with a high ironing ratio. The grid array pattern increased the load-carrying capacity of the lubricant more than the crossing pattern, as demonstrated by the simulations, thereby improving the ironing limit. The subsequent ironing of stainless steel cups revealed that when using a textured die with a grid array pattern and lubricant without the extreme pressure additive in comparison to an untextured die, the ironing limit increased by 6% and the average ironing load decreased by 35%. The seizure resistance was improved because the pockets on the surface structured by laser surface texturing improved the load-carrying capacity during ironing.

Development of Double-Insulated Ring Sensors for Hollow Pin Preload Measurement

The hinge mechanism of aviation flap is composed of joint bearing, single lug, double lugs, hollow pins and self-locking nuts, etc. This hinge mechanism has accurate requirements for the preload of the hollow pin. When no seizure of the joint bearing occurs, the bolts are required to have sufficient preload to clamp the inner ring of the bearing. Meanwhile, when the seizure of the joint bearing occurs, there shall be no movement between the bearing and pin shaft or the end face of the bushing shall arise. This requires that the tension of the hollow pin shaft shall not be too high, otherwise the friction torque isn’t easy to overcome. However, the method to directly measure the preload in the hollow pin is not available, and the influence law of preload decline on the seizure resistance of the bearings also can’t be evaluated. This paper presents a method suitable for measuring the preload of hollow thin-walled pin parts. By applying permanent piezoelectric thin film transducer onto the end face of the hollow pin, the standardization technology is used to measure the propagation time change of the ultrasonic signal generated by the transducer in the pin as a function of the temperature and preload, thus realizing the accurate measurement for the preload of the hollow pin during installation. Finally, the application verification is conducted by using the measurement method proposed in this paper. The results show that this method can effectively optimize the installation and service performance for the hollow pin.

Analysis of seizure-resistance-improvement mechanism of polymer additives by acoustic emission sensing

Analyses of the spectra of acoustic emissions produced by the deformation and fracture of frictional surfaces were used to identify the mechanisms by which polymer additives in lubricating oils improve seizure resistance. Analysis of the frequency spectra of the acoustic signal waveforms permitted the evaluation of interactions between surface asperities that were undetectable from changes in the coefficient of friction. The changes in acoustic emissions explain the action of viscosity modifiers in lubricants in relaxing the contact between surface asperities, and the sensing and analysis of acoustic emissions could provide a new method for analysing the action of lubricant additives.

Increase in ironing limit of stainless steel cups with lubricants containing ceramic particles

The seizure resistance in the ironing process of stainless steel cups was improved with lubricants containing Al2O3 particles, and the ironing limit of the cups was increased. The effects of suspending different concentrations of Al2O3 particles in paraffin based oils on increasing the ironing limit of SUS430 cylindrical cups before seizure were investigated using a lapped tungsten carbide die. By containing c = 2vol% of Al2O3 particles having nominal diameter d between 0.02 to 4 micrometres in an oil with a kinematic viscosity of 500 mm2/s, the ironing limit of the cup was 8% under a punch speed of 100 mm2/s. The limit was similar to the limit using a commercial low-viscosity oil with chlorine additive. The kinematic viscosity of the base oil was reduced. In d = 0.2 μm and c = 0.5vol%, the limit of the oil more than kinematic viscosity of 180 mm2/s was similar to the limit by the commercial oil. In d = 4 μm and c = 1vol%, the limit of the oil having more than kinematic viscosity of 100 mm2/s was effective. It was found that the seizure resistance in the ironing process was improved by the proper ironing conditions with lubricants containing particles.

Lafora disease: a case report

BackgroundLafora disease is a rare genetic disorder involving glycogen metabolism disorder. It is inherited by autosomal recessive pattern presenting as a progressive myoclonus epilepsy and neurologic deterioration beginning in adolescence. It is characterized by Lafora bodies in tissues such as brain, skin, muscle, and liver.Case presentationWe report a rare case of Lafora disease in a 16-year-old Albanian girl who presented at a tertiary health care center with generalized tonic–clonic seizures, eyelid twitches, hallucinations, headache, and cognitive dysfunction. She was initially treated for generalized epilepsy and received an antiepileptic drug. However, owing to resistance of seizures to this antiepileptic drug, a second drug was introduced. However, seizures continued despite compliance with therapy, and general neurological status began to deteriorate. The child began to have hallucinations and decline of cognitive function. She developed dysarthria and unsteady gait. When admitted to the hospital, blood tests and imaging examinations were planned. The blood tests were unremarkable. There was no relevant family history and no consanguinity. Electroencephalography showed multifocal discharges in both hemispheres, and brain magnetic resonance imaging revealed no abnormality. Axillary skin biopsy revealed inclusion bodies in apocrine glands. Consequently, the child was referred to an advanced center for genetic testing, which also confirmed diagnosis of Lafora disease with a positive mutation on NHLRC1 gene.Conclusions Even though rare as a condition, Lafora disease should be considered on differential diagnosis in progressive and drug-refractory epilepsy in adolescents, especially when followed by cognitive decline.

Alterations of Plasma Pro-Inflammatory Cytokine Levels in Children with Refractory Epilepsies.

Paediatric epilepsy is a multifaceted neurological disorder with various aetiologies. Up to 30% of patients are considered drug-resistant. The background impact of interfering inflammatory and neuronal pathways has been closely linked to paediatric epilepsy. The characteristics of the inflamed state have been described not only in epilepsies, which are considered prototypes of an inflammatory pathophysiology, but also in patients with drug-resistant epilepsy, especially in epileptic encephalopathies. The imbalance of different cytokine levels was confirmed in several epileptic models. Chemokines are new targets for exploring neuroimmune communication in epileptogenesis, which control leukocyte migration and have a possible role in neuromodulation. Additionally, prostaglandin E2 (PGE2) is an important effector molecule for central neural inflammatory responses and may influence drug responsiveness. We measured the serum interictal quantitative levels of chemokines (CCL2, CCL4, CCL11) and PGE2 in correlation with the seizure frequency and severity in controlled and intractable childhood epilepsies. Our refractory seizure group demonstrated significantly increased concentrations of eotaxin (CCL11) compared to the controlled epilepsy group. The higher level of CCL11 was correlated with an increased seizure frequency, while the PGE2 levels were associated with the severity of seizure and epilepsy, supporting the findings that proinflammatory cytokines may contribute to epileptogenesis and possibly have a role in developing seizure resistance.

Sliding wear response of ultrasonic-assisted stir-squeeze cast Al-Zn(-Mg) alloy/ZrO2p composite: wear mechanism and subsurface deformation

The character of hard ZrO2p in dry sliding wear of Al-Zn(-Mg) alloy was investigated in the cast and heat-treated conditions using a pin-on-disc wear tester at fixed sliding speed (3.5 m s−1) and varying applied pressure (0.5–2.125 MPa), giving special accentuation on the response parameters such as seizure resistance, wear rate, and bulk temperature rise. Hardness behavior was also studied for the same concerning materials in accordance with ASTM standards. The composites exhibited enhanced hardness, wear and seizure resistance, and greater temperature rise over the alloy. Indeed, the wear rate at preliminary stages increased with increasing applied pressure up to a transition limit beyond which it upsurged abruptly to greater value at the seizure pressure. Heat treatment also significantly improved the hardness, and resistance to wear and seizure. Amongst, heat-treated composite embedded with 4% ZrO2p yielded the highest hardness of 180 HV and seizure pressure of 2.125 MPa, respectively. The deformation in the subsurface was examined in terms of microhardness variation along the depth perpendicular to the worn surface. It was detected that the presence of ZrO2p not only enhanced the seizure resistance but also effectively hampered the extent of subsurface deformation at the seizure. The wear mechanism was prevalently governed through the establishment of the mechanically mixed layer (MML), oxide layer, cracking, and deformed subsurface.

Childhood Lennox-Gastaut Syndrome, Low Set Ears, Unilateral Cryptorchidism: A New Variant

Background: Childhood Lennox-Gastaut syndrome is a heterogeneous epileptic encephalopathy with onset between the age of one and seven years. It is associated with more than one seizure type that are drug-resistant, a slow spike-wave activity in the EEG recording and mental retardation .The syndrome was first described by William Gordon Lennox in 1950, and later by Henri Gastaut in 1966. The condition was first called “Lennox-Gastaut syndrome” by Ernst Niedermeyer in 1968. The association of Lennox-Gastaut syndrome with low set ears and cryptorchidism has not been reported before. Patients and Methods: A two and three months boy was referred late during February, 2022 because of seizures that started during the last week of December, 2021 and were not controlled with multiple anti-epileptic drugs. The diagnosis was made and an evidence-based therapeutic approach is described. Results: When the boy was first seen he was still experiencing frequent generalized tonic clonic seizures that may last for about ten minutes and myoclonic seizures, despite he was receiving four anti-seizure drugs in good doses including valproic acid, clobazam, levetiracetam, topiramate. The drugs made the boy sleepy most of the day. Brain MRI was performed during August, 2021 for the evaluation of developmental retardation showed normal findings. The presence of more than seizure type, the EEG recording, and the developmental and retardation together with resistance of seizures to polytherapy allowed confident diagnosis of Lennox-Gastaut syndrome. Anti-epileptics were replaced with other drugs and evidence-based agents were used for neuroprotection and improving development and mental retardation. Treatment was associated with a significant improvement. Conclusion: A new variant of childhood Lennox-Gastaut syndrome is reported and the experience with its early treatment is described.

Study on the microstructure and wear behavior of Mg-containing Al–12Sn–4Si alloys

Al–Sn–Si alloys have been widely used as bearing alloys in automotive engines. In those alloys, β(Sn) phase serves as the solid lubricant and Si particles are used to improve the hardness, fatigue resistance as well as seizure resistance. With the development of machinery, bearing alloys with higher load-carrying capacity and better tribological properties are demanded to meet the application under severe conditions. Adding appropriate Mg to the Al–Sn–Si alloy can effectively optimize the tribological properties. In this paper, the microstructure, mechanical properties and tribological properties of the Al–12Sn–4Si-xMg (x = 0, 0.5, 1, 1.5, all in wt.%) alloys were studied. The Al–12Sn–4Si-1.5 Mg alloy had the smallest grain size and more uniform microstructure than other specimens. The Al–12Sn–4Si-1.5 Mg alloy showed significantly better wear resistance than the Al–12Sn–4Si alloy at 2 N–70 N. The volume wear rates and friction coefficients at 15 N–70 N were lower than those at 2 N–8 N. The evolution of volume wear rate and friction coefficient with load was related to the evolution of tribolayer with load. The wear mechanism of the alloys was mainly oxidation wear, adhesive wear and fatigue wear, accompanied with abrasive wear.