Plasma Flame Research Articles

Excellent ablation resistance of Ti3AlC2 ceramics up to 1900 °C in nitrogen plasma flame

In this work, the ablation behaviors of Ti3AlC2 ceramics were investigated in a nitrogen plasma flame at various temperatures. The ablation mechanisms were determined by analyzing phase compositions, macroscopic morphology, and microstructure. As the ablation temperature increased from 1500 to 1900°C, the linear ablation rate increased from − 0.725–8.7 µm/s, while the mass ablation rate increased from− 0.095–2.103 mg/s. At the ablation temperatures below 1900 °C, an oxide layer mainly consisting of Al2TiO5 was formed on the ablated surface owing to the decomposition and oxidation of Ti3AlC2, which adequately protected the matrix. When the ablation temperature reached 1900 °C, the oxide layer melted and was blown away by the plasma flow, resulting in the loss of protection and the rapid increase in ablation rates. The results indicate that Ti3AlC2 ceramic exhibits excellent ablation resistance below 1900 °C and is potentially used as thermal protection material.

Mechanical and ablation properties of Cf/SiBCN-ZrB2 composites prepared by an in-situ reaction: Effect of carbon source

SiBCN ceramics were prepared by a novel inorganic method: the in situ reaction of amorphous SiBON and C. Differences in the mechanical and ablation properties of composites prepared from flake graphite and carbon black (denoted as Cf/CGZ and Cf/CBZ, respectively) were compared to find a suitable carbon source. The results showed that flake graphite is the optimal carbon source. The fracture toughness of the Cf/CGZ composite was 9.1 ± 0.4 MPa·m1/2, which is 23.0% higher than that of the Cf/CBZ composite. This is because the flake graphite promoted crack deflection. Furthermore, after exposure to a plasma flame with a heat flux of 6.68 MW/m2 for 300 s, the mass and linear ablation rates of the Cf/CGZ composite are 0.39 mg/s and − 0.19 µm/s, respectively, which is a decrease of 22.00% and 64.81%, respectively, as compared to those of the Cf/CBZ composite. This is because of the directional distribution of flake graphite, which improved the thermal conductivity, reduced the ablation surface temperature, and facilitated the formation of a dense ZrO2/SiO2 layer as an anti-ablation barrier.

Advances and Challenges in Combustion Control of Radio Frequency Oscillating Plasma Discharge

Article Advances and Challenges in Combustion Control of Radio Frequency Oscillating Plasma Discharge Linyan Wang , Xiao Yu , Graham Reader , and Ming Zheng * Department of Mechanical, Automotive and Materials Engineering, University of Windsor, 401 Sunset Avenue, Windsor, N9B 3P4 Ontario, Canada * Correspondence: mzheng@uwindsor.ca Received: 18 July 2023 Accepted: 13 September 2023 Published: 20 September 2023 Abstract: Oscillating plasma (corona) ignition is a promising technique for producing a larger initial ignition volume for achieving cleaner combustion. The oscillating plasma system provides a quick response to the ignition command compared with the conventional transistor-coil-ignition systems (TCI). Subsequently, the shorter combustion duration contributes to further improvement of engine efficiency under lean/diluted conditions. The challenges of oscillating plasma ignition appear under elevated background pressures, mostly owing to fewer plasma streamers and even void discharge, thus the advantage of oscillating plasma discharge over spark discharge is compromised. To suffice the industrial applications, the challenges of plasma generation and control platforms are investigated and discussed in this work. The challenges include ignition control, background condition impacts, and other external disturbances. A flexible modulation for oscillating plasma generation is established, with the measurements of discharge voltage and current. High-speed imaging, simultaneous with electrical waveform measurements is applied to record the plasma formation and flame propagation. This research provides advances in the ignition control for the oscillating plasma discharge, adding a foundation and reference for the oscillating plasma diagnostics under engine-like conditions with variations of pressure, temperature, gas composition, and flow pattern.

Ablation resistance of Ti2AlC ceramics at 1600 °C in nitrogen plasma flame

In this study, the ablation behaviors of high-purity and dense Ti2AlC ceramics were investigated using a nitrogen plasma flame at 1600 °C. The macromorphology, microstructure, and phase compositions of the Ti2AlC ceramics were systematically investigated at ablation times of 60–180 s. At the longest ablation time of 180 s, the linear ablation rate and mass ablation rate are 3.09 μm/s and −0.473 mg/s, respectively, which indicate noteworthy ablation resistance. The ablated cross-sections of the samples can be classified into three layers: a surface oxide layer, transition decomposition layer, and matrix layer. The surface oxide layers formed at different ablation times are composed of Al2TiO5 and TiO2, and the transition decomposition layer comprises mainly TiC and Al2O3 with pores and cracks. The high ablation resistance of the Ti2AlC ceramics is primarily due to the formation of the surface oxide layer, which effectively prevents oxidation and plasma flow erosion.

Ablation behavior of La2O3 modified C/C–ZrC composites fabricated by precursor infiltration and pyrolysis

La2O3 modified C/C–ZrC composites were produced by precursor infiltration and pyrolysis (PIP) technique, and the ablation resistance was tested in plasma flame at 1700 and 2400 °C. Results displayed that the density of the composites was ∼1.90 g/cm3, and ZrC and La2O3 were uniformly distributed in them. At 2400 °C, the linear and mass ablation rates of La2O3 modified C/C–ZrC composites were 8.89 ± 0.82 μm/s and 0.21 ± 0.01 mg/s, respectively. The positive effect of La2O3 was to promote the liquid phase sintering of ZrO2, which was helpful to promote the formation of an inlaid La–Zr–O molten layer that acted as a protective barrier. At 1700 °C, the composites exhibited minimal linear and mass ablation rates of 0.41 ± 0.14 μm/s and 0.04 ± 0.01 mg/s, respectively. At this temperature, La2O3 promoted the solid phase sintering of ZrO2 to form an intact La–Zr–O particle-stacked layer, and the intact oxide layer positively protected the composites.

고엔탈피 플라즈마 및 초고속 화염 환경에서의 니들 펀칭 C/C 복합재의 삭마 특성 분석

재진입 시 공력 가열 환경에 노출되는 우주 비행체는 열보호 시스템(Thermal Protection System, TPS)이 적용된다. 따라서 재진입 환경을 구현할 수 있는 지상 시험 장비를 통한 열보호 재료의 시험 평가가 필요하다. 본 논문에서는 다양한 장비 중 아크 가열 풍동(Arc-heated Wind Tunnel, AWT)과 초고속 화염(High-Velocity Oxygen Fuel, HVOF) 시스템을 활용하여 NPCC(Needle-Punching Carbon/Carbon)재료의 삭마 시험을 수행하였다. AWT 결과와 비교하면 HVOF 시험의 표면 온도가 정상 상태로 급격하게 증가하였으며, 이로 인해 삭마량이 크게 발생하였다. 또한 HVOF 유동의 높은 질량 유속으로 인해 표면 거칠기가 증가함을 확인하였다. 이와 같이 공통 열유속 영역에서 고엔탈피 플라즈마 및 초고속 화염환경에 따른 삭마 특성의 상관관계를 도출하였다.

Ablation behaviors and mechanism of ZrC-SiC-Si/SiC-Si double-layered coatings on C/C composite under plasma flame at 3000 °C

To improve the ablation performance of C/C composite at 3000 °C, a ZrC-SiC-Si/SiC-Si double-layered coatings (ZSS/SS) was prepared by slurry dipping-carbonization and gaseous silicon infiltration. During ablation, a competition between mechanical denudation and oxidation derived thickening occurred. The ZSS/SS coating possessed a superior ablation resistance showing lowest linear ablation rate of 0.53 µm/s in 90 s with a parabolic rate constant Kp (0.053 µm/s3). The excellent performance was attributed to good self-sealing of oxidation derived glassy, thus no micro-cracks were observed. However, the Kp became worse to be 0.131 for long-term ablation because of dominant mechanical denudation.

Evaluation of blood lead measurements by the 6-year external quality assessment program in China

BackgroundBlood lead is an important clinical indicator. A typical tool for promoting standardisation or harmonisation is external quality assessment (EQA). Therefore, the National Centre for Clinical Laboratories (NCCL) in China launched the EQA Program for blood lead measurement in 2006 to assess its standardisation process. MethodsBlood lead EQA samples tested for homogeneity and stability were sent to participating laboratories. The return data were grouped according to the detection method. The robust mean value, robust coefficient of variation (CV) and standard uncertainty were calculated according to ISO 13528. The evaluation criteria were determined based on a thorough analysis of the previous pass rate and the current detection level. Overall trends in the blood lead EQA program over 6 years were investigated by calculating the pass rates of participating laboratories. We compared the pass rates and current issues of different detection methods and analysed the target values, bias and CV results of mainstream detection methods. ResultsA total of 4,283 laboratories participated in EQA programs from 2017 to 2022. The pass rates were generally increasing while the inter-laboratory mean CVs were decreasing. For samples with varying concentrations, the higher the concentration, the smaller the CV. According to the evaluation criteria, the most used measurement methods, Graphite Furnace Atomic Absorption Spectrometry (GFAAS) and Tungsten Ship Atomic Absorption Spectrometry (TSAAS) demonstrated better performances than Differential Potentiometric Stripping (DPS), Inductively Coupled Plasma Mass Spectrometry (ICP-MS) and Flame Atomic Absorption Spectrometry (FAAS). Furthermore, DPS, ICP-MS and FAAS outperformed Anodic Stripping Voltammetry (ASV). ConclusionOur study provides reliable information on the standardisation of blood lead measurement procedures for manufacturers and clinical laboratories. Further improvements for standardisation are still required to make laboratories more patient-centred.

Preparation, mechanical properties and long-term ablation resistance of Cf/SiBCN–ZrB2 composites

The Cf/SiBCN–ZrB2 composites were prepared by dipping and winding combined with reactive hot pressing. The flexural strength and fracture toughness reached 261 MPa and 11.96 MPa • m1/2, respectively, through continuous carbon fibers debonding, pulling and bridging mechanisms. Excellent mechanical properties ensured that the Cf/SiBCN–ZrB2 composites remained intact after exposure to a plasma flame with a heat flux of 9.37 MW/m2 for 300 s, with the mass and linear ablation rates of 1.78 mg/s, 1.01 μm/s, respectively. The excellent ablation resistance was due to the formation of dense oxide layers separating the matrix from the plasma flame. The SiO2 formed in the low-temperature areas away from the center was the main ablation-resistant barrier, while the ZrO2/SiO2 double oxide layer formed in the high-temperature region at the center was the major ablation-resistant barrier.

Effects of air plasma flame on the ZrB2-based UHTC coatings: Microstructure, phase evolution and ablation resistance

As for the air plasma sprayed ZrB2-based coatings, B content change caused by inevitable oxidation is predictable but commonly ignored. Affected by air plasma flame, the B element loss and residual B2O3 in the sprayed ZrB2 coating were observed. Moreover, how the B content change affects the microstructure, phase evolution, and ablation resistance (2.4 MW/m2, 60 s) of ZrB2-based coatings with different secondary phases (SiC, MoSi2, and TaC) was investigated. The B element loss contributed to the increase in surface temperature and the decline in the sintering degree of the ZrO2 layer. The evaporation of residual B2O3 caused damage to the coating structure in the form of pores, whose negative effect was enhanced and reduced by MoSi2 and TaC secondary phases, respectively. This work will provide some insight into thermally sprayed non-oxide ceramic coatings in the atmosphere.

Nitrogen plasma-induced crystallization of anodic TiO2 nanotubes for solar photoelectrochemistry

Anodic TiO2 nanotubes have gained tremendous interest due to the high specific surface area and facile growth with potential in large scale production. Their geometric features such as length, diameter, wall thickness or spacing between adjacent nanotubes can be tailored through the processing parameters maintained during the anodization. However, the as-anodized nanotubes are amorphous and for practical applications they require phase transformation. Usually, it is realized via furnace annealing. Nonetheless, taking into account the heating and cooling stages the whole process can take several hours. Moreover, furnaces usually use resistive heating, hence crystallization in furnace can be recognized as a highly time- and energy-consuming process, and the size of the sample is limited by the dimensions of uniformly heated area in the furnace. Here we show fast 30-second nitrogen plasma-induced crystallization of TiO2 nanotubes depending on the position in the plasma flame. We found a comparable photoresponse to the furnace annealed TiO2 nanotubes without significant change in their ordered morphology. The proposed method shows promising results regarding the reproducibility and stability of the fabricated photoanodes. We anticipate that the present work will contribute to wider applications of plasma for modifications of functional materials, especially in terms of the phase transitions.

Conversion mechanism of thermal plasma-enhanced CH4-CO2 reforming system to syngas under the non-catalytic conditions

Thermal plasma activation of CH4-CO2 reforming (CRM) to syngas under non-catalytic conditions is an efficient and clean technology for the large-scale utilization of hydrocarbon resources and the conversion of greenhouse gases. This study investigates the equilibrium state and transformation mechanism of a CRM reaction system activated by thermal plasma through experimental, thermodynamic, and kinetic analyses. The experimental results illustrated that the CO2 conversion rate and H2 selectivity showed a downward trend with an increase in the CO2/CH4 molar ratio, whereas the CH4 conversion rate and CO selectivity showed the opposite trend. When CO2/CH4 molar ratio was 6/4, the selectivity for CO and H2 increased to 87.0 % and 80.8 %, respectively. Excess CO2 promotes the partial oxidation of CH4 to eliminate carbon deposition, resulting in an H2/CO molar ratio value closer to 1. Thermodynamic results show that the thermal-plasma-initiated CRM reaction can reach thermodynamic equilibrium more easily than the conventional catalyzed reactions, achieving much higher feedstock gas conversion without carbon deposition. The kinetic results obtained from the PSR model revealed that CH4 and CO2 were cleaved to form free radicals at the instant of contact with the plasma flame. O, H, and other particles generated in the form of free radicals rapidly collided with each other and transformed into CO and H2, accelerating the reaction process. The results presented in this study will help reveal the transformation mechanism of the CRM reaction activated by thermal plasma under non-catalytic conditions and provide a new perspective for studying CRM reactions.

Tuning ceramic content, mechanical and ablative properties of C/C–ZrC-ZrxCuy composites via using various C/C skeletons

C/C–ZrC-ZrxCuy composites were prepared by pressure-assisted reactive melt infiltration with Zr2Cu alloy as an infiltrator. The mechanical and ablation properties of C/C–ZrC-ZrxCuy composites were tuned by applying various C/C skeletons (1.28, 1.40, 1.58, and 1.73 g/cm3). When the C/C skeleton density increased from 1.28 to 1.73 g/cm3, the density of the composites decreased gradually. Additionally, due to the higher ceramic content, composites with low skeleton density (1.28, 1.40 g/cm3) exhibit a higher compressive and flexural strength. The fabricated composites with a skeleton density of 1.28 g/cm3 possess better mechanical properties and ablative properties at 2800 °C. After plasma flame ablation for 54 s, the linear and mass ablation rates of the composites are 33.70 ± 1.33 μm/s and 22.39 ± 2.99 mg/s, respectively.

Plasma Electrochemistry: Redox Reactions in Gases

Electrochemistry underpins numerous commercially important processes ranging from energy generation to sensors and coating deposition. A common and –so far– essential feature of all these processes involve a redox active species dissolved in a solvent which serves to allow charge exchange between electrodes. Rather than being inert, the solvent is without exception redox-active at extreme potentials and thus restrict the breadth of observable reactions to a narrow potential window of approx. -2.5 to +2.5 V vs. NHE. Gaseous electrolytes have typically been ignored due to their feeble electrical conductivity. However, recently with the advent of new accessible approaches to form stable plasmas, these electrically conducting gases are attracting some significant interest and are now being investigated as exotic electrochemical environments. The scope of this work is to apply the well-healed cornerstones of electrochemistry developed almost exclusively in liquids, to the new context of gaseous plasma.The defining property of plasmas is presence of free electrons; because of this they may be considered as both electrodes or electrolytes1&2. We describe results supporting both modes. As electrodes, we show that metal oxides on surfaces may be reduced to zero valent metals using a helium atmospheric plasma jet.3&4 We show that free electrons do indeed reduce a copper oxide film, which may be carefully controlled by surface bias.5 A gaseous flame doped with electroactive species may be considered as electrolytes. Using a three-electrode system6, we may measure unique voltammograms for a series of small organic molecules and amino acids.7 Except for leucine and isoleucine, all were distinguishable. The reduction signatures originate from specific electron attachment reactions of radicals formed via incomplete combustion and fragmentation of the parent molecules. In this case without a solvent we have an extended potential window and our voltammograms extend between 0 and -10 V, which gives unprecedented access to chemistry not previously accessible in liquids. Moreover, mass transport properties are far better than in liquids, as such the fluxes of electroactive species to the electrode a much greater. References Rumbach, P.; Bartels, D. M.; Sankaran, R. M.; Go, D. B., The solvation of electrons by an atmospheric-pressure plasma. Nature Communications 2016, 6, 7248.Elahi, A.; Fowowe, T.; Caruana, D. J., Dynamic Electrochemistry in Flame Plasma Electrolyte. Angewandte Chemie-International Edition 2012, 51 (26), 6350-6355.Sener, M. E., Quesada Cabrera, R., Parkin, I.P., Caruana, D. J., Facile formation of black titania films using an atmospheric-pressure plasma jet, Green Chemistry 2022, 24, 2499-2505.Sener, M. E., Palgrave, R., Quesada Cabrera, R., Caruana, D. J., Patterning of Metal Oxide thin Films using H2/He Atmospheric Pressure Plasma Jet. Green Chemistry 2020, 22, 1406-1413.Sener, M. E.; Caruana, D. J., Modulation of copper(I) oxide reduction/oxidation in atmospheric pressure plasma jet. Electrochemistry Communications 2018, 95, 38-42.Fowowe, T.; Hadzifejzovic, E.; Hu, J. P.; Foord, J. S.; Caruana, D. J., Plasma Electrochemistry: Development of a Reference Electrode Material for High Temperature Plasma. Advanced Materials 2012, 24 (47), 6305-6309.Calleja, M.; Elahi, A.; Caruana, D. J., Gas phase electrochemical analysis of amino acids and their fragments. Communications Chemistry 2018, 1, 48.

Evaluation on the microstructure and thermal infrared emissivity of Ca2+-doped ytterbium chromate coating deposited by saucer-shaped porous feedstocks for high-temperature thermal protection

A high infrared emissivity coating with porosity of 16.2 % was deposited on Ni-based alloy by saucer-shaped porous feedstocks using the atmospheric plasma spraying technique. The solid-phase reaction method was employed to synthesize Ca2+-doped YbCrO3 ceramic powders, and then the saucer-shaped porous feedstocks were obtained by electrostatic spraying accompanied by heat treatment, and the conventional spray drying feedstocks were used as comparison. Compared with the conventional structural coating, the coating achieved by saucer-shaped feedstocks shows higher porosity and surface roughness due to the insufficient melting of the feedstocks with larger diameters in the plasma flame. Therefore, the coating achieved by saucer-shaped feedstocks exhibits a bimodal organization similar to that of nanostructured thermal barrier coatings. Compared with the conventional coating, the coating with new structure shows a higher emissivity value of 0.9460 at 1–14 µm waveband at room temperature due to the higher surface roughness (7.12 μm). Moreover, the average emissivity of coatings with roughness ranging from 0.93 µm to 7.12 µm is all above 0.91. More importantly, although the infrared emissivity of all coatings with different roughness decreases with the increase of temperature, they still remain above 0.77 at 1–14 µm when the temperature reaches 1200 °C.

Comparative study of some macro & micro elements in milk samples from Abuja, Nigeria using microwave plasma atomic emission spectroscopy (MP-AES) and flame atomic absorption spectroscopy (F-AAS) methods

A comparative study was carried out for the determination of calcium, magnesium, iron and zinc contents in two brands of powdered milk samples, using the Microwave Plasma Atomic Emission Spectroscopy (MP-AES) and Flame Atomic Absorption spectroscopy (F-AAS) methods. The powdered milk samples were collected and placed in a muffle furnace at 550°C for 6 hours, and the ash contents obtained was used for the sample preparation. The percentage recoveries for the spikes were as follows: for MP-AES determination; the recoveries for the milk samples were within the range (116.9 – 163.1%) for calcium; (51.8 – 78.8%) for magnesium; (110.9 – 125.4%) for iron; (90.7 – 92.9%) for zinc. For FAAS determination; the recoveries for the milk samples were within the range (51.1 – 83.6%) for calcium; (52.2 – 61.9%) for magnesium; (77.7 – 84.8%) for iron; (46.5 – 71.7%) for zinc. The percentage recoveries showed a better recovery with MP-AES than the F-AAS method. The analysis of variance conducted using One way ANOVA method shows that there is no significant difference between the two methods used for the analysis, as the P-values (calculated probability) obtained were higher than 0.05. The values obtained for Ca, Mg, Fe and Zn content shows that only Ca was found to be within WHO/FAO standard, while Mg, Fe and Zn were found to be below the WHO/FAO standard. It is highly recommended that a 100g of any of the powdered milk used for the research work be consumed per day in order to meet up with the RDA per day, or other sources of these elements to be considered.Â

Microstructures, thermophysical properties and thermal cyclic behaviors of Nd2O3 and Sc2O3 co-doped LaMgAl11O19 thermal barrier coating deposited by plasma spraying

In this study, La1-xNdxMgAl11-xScxO19 (x = 0.1, 0.2, 0.3; abbreviated as LNMAS-1, 2, 3) coatings which are supposed to possess better properties than LaMgAl11O19 (LMA) were plasma-sprayed and their high-temperature performance were comparatively investigated. Results show that addition of Nd3+ and Sc3+ as dopants to LMA endows corresponding coatings with reduced thermal conductivity and enhanced thermal expansion coefficient, while maintaining advantageous phase stability, although still being subjected to amorphization in plasma flame and following crystallization upon high-temperature service. Furthermore, the doping could cause adherence increasing between topcoat/bondcoat, benefiting from improved melting condition, especially in LNMAS-2 and LNMAS-3 coatings, which is related to the specific powder morphology and lowered melting point. During exposure to 1350°C, mechanical performance and structure integrity of doped free-standing LNMAS coatings can be well preserved even after 400 h aging. In thermal cyclic fatigue test, LNMAS-2 and LNMAS-3 coatings undertake thermal cycling lifetime of ∼181 and 191 cycles at 1100°C, respectively, 40% durable than that of LMA coating. These preliminary results suggest that LNMAS-2, 3 might be promising candidates for advanced thermal barrier coating applications.

THERMAL SPRAYING AND RELATED TECHNOLOGIES FOR THE SURFACE MODIFICATION OF AL ALLOYS: REVIEW

Aluminum (Al) and its alloys are attractive for a variety of applications due to its advantages like light weight, ease of processing, and high thermal/electrical conductivities. However, it suffers short comings in terms of strength, wear resistance, and corrosion resistance. Thermal spray processes are widely used techniques for the surface property improvement like thermal, wear, and corrosion resistances of aluminum and other light metals. This paper summarizes the recent developments in thermal spraying and related technologies. Plasma spraying, flame spraying, and arc spraying are the chief thermal spraying techniques, whereas the HVOF and D-gun processes are the derivatives of flame spraying process. The cold spraying technique is an emerging coating technique where the particles are heated to a temperature lower than their melting point travel at high velocity and coat on impact with the target material by plastic deformation. Different parameters like heat source characteristics, coating material properties, substrate properties, and spray torch operating circumstances affect the coating microstructure and properties.

Microstructure, mechanical and anti-ablation properties of Mg-modified C/C–ZrC–SiC composites prepared by sol-gel technology

Mg-modified C/C–ZrC–SiC composites were fabricated by a sol-gel process, and the influences of the Mg/(Zr + Si) molar ratio on the microstructure and the mechanical and anti-ablation properties of the composites were investigated. The results showed that Mg addition not only optimized the distribution of surficial ceramic particles but also improved the flexural strength of composites by inhibiting the ceramization of fibres. Fabricated Mg/(Zr + Si) with a molar ratio of 0.040:0.18 increased the flexural strength of the composite from 173.15 MPa to 331.22 MPa, and the elastic modulus ranged from 11.46 GPa to 23.09 GPa. After plasma flame ablation for 180 s, this composite also showed excellent anti-ablation performance with linear and mass ablation rates of 3.91 μm/s and −0.23 mg/s, respectively. The superior ablation property was ascribed to the formation of a consecutive oxide layer constructed by a viscous mixed liquid consisting of liquid Mg–Si–O and Zr–Si–O phases and the robust skeleton of the coarsening ZrO2.

Study on LIBS Standard Method via Key Parameter Monitoring and Backpropagation Neural Network

This paper proposes a method based on key parameter monitoring and a backpropagation neural network to standardize LIBS spectra, named KPBP. By monitoring the laser output energy and the plasma flame morphology and using the backpropagation neural network algorithm to fit the spectral intensity, KPBP standardizes spectral segments containing characteristic lines. This study first conducted KPBP experiments on the spectra of pure aluminium, monocrystalline silicon, and pure zinc to optimize the KPBP model and then performed KPBP standardization on the characteristic spectral lines of a GSS-8 standard soil sample. The spectral intensity relative standard deviations (RSDs) of Al 257.51 nm, Si 298.76 nm, and Fe 406.33 nm dropped from 12.57%, 16.60%, and 14.10% to 3.40%, 3.20%, and 4.07%, respectively. Compared with the internal standard method and the standard normal variate method, KPBP obtained the smallest RSD. The study also used a GSS-23 standard soil sample and a Beijing farmland soil sample to conduct KPBP optimization experiments. The RSD of spectral intensity was still significantly reduced, proving that the KPBP method has stable effects and wide applicability to improve the repeatability of LIBS soil analysis.