Chemical Composition Of Steel Research Articles

The influence of 3D printing mode on the chemical composition and structure of 30HGSA steel

The authors carried out the study of the influence of 3D printing modes on the structure and chemical composition of 30HGSA steel (chromansil) samples produced by the method of additive electric arc surfacing. To study the influence of the electric arc surfacing mode on the chemical composition of the steel under study, an optical emission analysis of the samples was carried out. The influence of the surfacing mode on the resulting structure was assessed over the entire height of the deposited walls at magnifications of ×50, ×100, ×200 and ×500. Optical emission analysis identified a change in the material chemical composition associated with the loss of chemical elements. It was found that the degree of loss of C, Cr and Si increases almost linearly and is directly proportional to the surfacing heat input (Q, J/mm). The exact influence of an increase in the surfacing heat input on the Mn content was not found, but a relationship between the degree of its loss and the voltage (U, V) during surfacing of samples was identified. Microstructural studies of all samples did not reveal a large number of systemically formed structural defects characteristic of cast and welded products (pores, shrinkage cavities, etc.), which confirms the high quality of the metal in goods produced by electric arc surfacing. Analysis of micrographs taken in different areas of the samples allowed determining that the metal microstructure does not undergo significant changes under different surfacing modes; the main tendencies in changes in the structure along the height of the sample are preserved. All samples demonstrated the formation of a highly dispersed structure, regardless of the 3D printing parameters. The most favorable metal structure, suitable for subsequent use in the production of goods using additive manufacturing, was recognized as the structure of the sample deposited using mode No.5 (I=160A, U=24V, Q=921.6J/mm). This mode can be used for further study of the problems of additive electric arc surfacing of 30HGSA steel.

Phase Transformations after Heat Treating an As-Cast Fe-30Mn-8.8Al-0.3Si-0.15C Steel

The phase transformations in an as-cast Fe-30Mn-8.8Al-0.3Si-0.15C steel were analyzed experimentally and numerically with a Calphad-based method during heat treatment. The nonequilibrium phases were determined using the Thermo-Calc Scheil module and the equilibrium phases with Themo-Calc based on the steel chemical composition. The precipitated phases were analyzed with TC-PRISMA using the chemical composition, nucleation site, and temperature among other factors. An ingot of this chemical composition was vacuum-melted using pure elements under an Ar gas atmosphere. As-cast steel specimens were annealed and solution-treated, quenched, and then aged at different temperatures. Heat-treated specimens were analyzed by different techniques. The results indicated that the microconstituents are the α and γ phases for the as-cast, homogenized, and quenched conditions. The main difference among these conditions is the distribution and size of the γ phase, which produced a change in hardness from 209 to 259 VHN. In contrast, the aging treatment at 750 °C caused a decrease in hardness from 492 to 306 VHN, which is attributable to the increase in volume fraction of the γ phase. On the other hand, the aging treatment at 550 °C promoted precipitation hardening from 259 to 649 VHN because of the κ precipitate formation. The calculated results for the different heat treatments with the Calphad-based method agreed well with the experimental ones. In addition, the intragranular precipitation of the κ phase could be simulated using the nucleation and growth and coarsening mechanisms based on a Calphad method.

Computer modeling of steel chemical composition to optimize steel production by combining heats

Computer modeling of steel chemical composition to optimize steel production by combining heats

DEVELOPMENT OF CRITERIA FOR EVALUATING STEEL REFINING PROCESSES USING INTERATOMIC INTERACTION PARAMETERS IN MELTS

To evaluate the efficiency of steel refining processes, the results of the physicochemical interaction of elements in the metal-slag system of ten steel grades smelted in modern conditions in Ukraine were analysed. As a result of the analysis of the patterns of changes in the distribution coefficients of sulphur and phosphorus depending on the chemical composition of steel and slag, physicochemical criteria for assessing the degree of completeness of ion exchange processes during steel dephosphorisation and desulphurisation have been developed using integral parameters of interatomic interaction in melts. Along with the use of integral physicochemical parameters of the chemical and charge state of the system ZY, e and Ze, the key role of the influence of the "recharge" parameter of the element ∆Ze on the process of sulfur and phosphorus distribution between metal and slag is shown and its use as a criterion for assessing the degree of deviation of the system from equilibrium is substantiated.

A MICRO-COOLED HIGH-STRENGTH WELD FOR HEAVY TRANSPORT MEANS

This paper focuses on the technical problem of repairing the main operating elements of heavy vehicles (semitrailers, dumps, and drums). If these vehicles are in service, significant changes in work schedules can occur, and costs can be generated immediately. Therefore, using the correct technology for repairs is crucial to minimizing financial and logistic difficulties. The article aims to analyze the mechanical properties of an MMA (Manual Metal Arc) welding (covered electrodes) joint made of Hardox 450 steel. This kind of material has a martensitic microstructure, which is difficult to weld because of changes in the components to the other ones during the joint process. Other inconveniences are related to the different chemical composition of steel and covered electrodes, their mechanical resistance, and thermodynamic conditions (consisting of the pre-heating temperature and the cross-pass temperature). Therefore, the joint quality should be determined using a few methods. In this case, NDT (magnetic and radiographic tests) and DT (microstructural analysis and static as well as fatigue tests) were used. All obtained results have enabled the proposed guides for the MMA welding of the steel grade. This is indicated as follows: (1) the method of bevelling the sheets before welding should be used, (2) pre-heating is necessary at temperature levels of 100 C and 125 C, and (3) the recommended interstitial temperature is between 170 C and 200°C.

Цифровые измерения неметаллических включений в стали

The experience of many-year research has shown that optimizing the steel chemical composition and microstructural characteristics, as well as reducing its contamination with non-metallic inclusions (NMI), it is possible to significantly increase the corrosion resistance of oilfield pipeline steels and increase the time of their trouble-free operation. The influence of complex NMIs on the steel corrosion resistance is determined by both the chemical composition of NMIs and their quantitative ratios. Therefore, obtaining metal products of the required quality is possible only when using the “control by structure” principle. In the work, based on the analysis of brightness fields of images (on a sample scale) in 256 shades of gray, the authors proposed digital, metrologically supported procedures for measuring the NMI heterogeneity of low-carbon oilfield steels: eliminating the heterogeneity of field illumination, justifying the criteria for binarization and noise filtering. For low-carbon steels of various types of melting, the authors identified the key role of dispersed non-metallic inclusions ranging in size from 5–10 μm2 to 2 nm2 in the formation of the corrosion resistance of steels. This may explain why, in some cases, there is no interrelation between the corrosion rate and the fracture resistance of steels, the formation of which is determined by larger particles. When representing the NMI as a set of random points on the plane, the distribution of distances between the nearest ones is estimated based on Voronoi polyhedra statistics. The study shows that an increase in the kurtosis coefficient of distributions of polyhedra areas is accompanied by an increase in the corrosion rate of the steels under study. This indicates the negative impact of heterogeneity in the arrangement of dispersed NMIs on the corrosion resistance of steels.

Effect of Pipe Steel Chemical Composition and Structural Characteristics on Corrosion Resistance under Western Siberia Oilfield Pipeline Operating Conditions

Effect of Pipe Steel Chemical Composition and Structural Characteristics on Corrosion Resistance under Western Siberia Oilfield Pipeline Operating Conditions

Occurrence of characteristic defects of grinding balls from rejects of continuously cast billets of rail steel

On the basis of metallographic studies, the authors determined the characteristic defects of grinding balls rolled from the rejects of continuously cast billets of K76F rail steel. Relationship of the presence of internal defects of the balls with their impact resistance was established. Defects in the form of internal cracks with accumulations of non-metallic inclusions in the area of their localization and flocks have the greatest impact on the reduction of balls impact resistance. Such defects are the cause of balls destruction during impact resistance tests in 62 and 17 % of cases, respectively. The effect of internal cracks without significant accumulations of non-metallic inclusions and quenching microcracks located along the boundaries of the phase interface was estimated at 12 and 9 %. The regularities and mechanism of influence of the rejects chemical composition of K76F rail steel billets on the probability of destruction of the balls produced from them during impact resistance tests were established. An increase in sulfur content in the billets of the studied rail steel reduces impact resistance of the balls produced from them, as it contributes to formation of non-plastic sulfides that concentrate in the area of internal cracks. An increase in hydrogen content in rail steel naturally contributes to an increase in probability of formation of the flocks, which significantly reduce the balls stability to shock loads. An increase in carbon content in the initial billets affects the increase in probability of destruction of K76F steel balls during copra tests. It is explained by formation of cementite-type carbides when carbon content corresponding to the eutectoid steel is reached. In general, the relative degree of influence of the K76F rail steel chemical composition on impact resistance of grinding balls is 48 %.

Micromechanical Modeling of Strain‐Hardening Behavior in Dual‐Phase Steels

A mathematical model is developed to consider the impact of microstructural parameters, including the volume fraction and the average particle size of martensite, on the flow stress and strain‐hardening behavior of dual‐phase microstructure. In this regard, the micromechanical approach is applied for partitioning the stress and strain in ferrite and martensite. Martensite carbon content and geometrically necessary dislocations, generated from austenite‐to‐martensite transformation, and strain accommodation at the ferrite–martensite interface, are involved to modify the partitioned stress of martensite and ferrite, respectively. Having partitioned stress in each phase, the global stress is estimated as the function of steel chemical composition, ferrite grain size, martensite particle size, aspect ratio, and volume fraction. To evaluate the applicability of the proposed model, four dual‐phase steels containing 12, 25, 34, and 48% volume fractions of martensite are prepared from the intermediate quenching process, and then after the strain‐hardening stages are investigated. Comparing the experimental result and model output reveals that the presented model shows good predictive capabilities to identify strain‐hardening stages and estimate the inverse of the strain‐hardening exponent.

INVESTIGATION OF CORROSION AND ADHESION BEHAVIORS OF BORONIZED ASP® 2012 STEEL

Tool steels are extensively used in sheet metal forming dies in order to prolong the life of dies and reduce the cost of production. Powder metallurgy tool steels are also alternatively preferred because of their low-risk metallurgical behavior owing to their compositions by which bulk steel would be difficult to produce, such as high amount of carbides or high alloying elements. Such advantage is desired if the steel has a narrow range of fine grain sizes and is less metallurgically affected by the heat treatment process due to having large surface area of fine grains. In this study, ASP® 2012 powder metallurgy steel containing high amounts of Si, Cr, Mo and W was selected for boronizing by the boron-giving thermochemical process. The boride layers on the surface of ASP® 2012 tool steel were metallographically characterized by various characterization techniques including adhesion strength test, SEM and XRD. The effects of corrosion kinetics and chemical composition of steel on the amount and types of boride layers formed on P/M steel of ASP® 2012 after powder-pack boriding were investigated. The results indicate that, according to the Rockwell-C indentation test, the best adhesion in the boride layer was obtained in samples borided at 850°C for 4 h, while the worst adhesion was obtained in ASP® 2012 steel boronized at 950°C for 4 h. Corrosion rates of boronized ASP® 2012 steel were decreased compared to nonboronized ASP® 2012 steel.

Chemical composition and weld cooling time effects on heat-affected zone hardness of line pipe steels

In the past few years, the pipeline industry in North America has faced a reported increase of pipeline girth weld failures predominantly in grade X70 pipe welded with cellulosic consumables. Weld strength matching and HAZ softening were two factors believed to have contributed to the concentration of strain during, or soon after, construction which ultimately lead to an overload failure of the girth welds. The work reported in this paper aimed to establish and clarify the correlation between steel chemical composition and the HAZ hardness in typical production girth welds and a range of weld thermal simulations. The first stage was to calibrate the influence of weld cooling rate of both thermal simulations and real welds in steels over a wide range of chemical composition, typical of commercial high strength API pipe. Second, the influence of Pcm, carbon content, Mo content and cooling time in terms of minimum and maximum hardness were investigated. The comparison between simulated HAZ's and real welds showed that thermal simulation produces samples that adequately duplicate the real condition in terms of maximum and minimum hardness and can accurately assess both hardening & softening which occur in different regions of the HAZ. The simulated samples provided increased areas of different HAZ regions in order to more accurately identify the range of hardness values across the HAZ which was then correlated to real weld hardness profiles. It is concluded that ultimate hardness in the HAZ is directly related to steel chemical composition in terms of Pcm and weld cooling rate. It is however apparent that the relative percentage change in hardness from the original parent pipe hardness (also called % HAZ softening), which is important in determining the strain capacity of the weld joint, is principally dependent upon steel processing, especially the degree and severity of thermomechanical processing. This is evident by the fact that same API pipe grades have a wide range in chemical composition and most importantly Pcm, and the response to field welding conditions can be quite different depending on weld heat input, pipe wall thickness and preheat, all of which define the weld cooling rate.

The coupling machine learning for microstructural evolution and rolling force during hot strip rolling of steels

Microstructural evolution during hot rolling, which is complex and unperceptive but has direct effects on rolling forces, determines the final microstructure and mechanical properties of steel products. In this paper, a comprehensive set of machine learning (ML) models was developed through rolling forces to reveal the evolutions of recrystallization and grain size of austenite, in which the grain size was estimated by considering the grain shape effect after each rolling pass. By using the backpropagation neural network (BPNN) and genetic algorithm (GA) combined with industrial data, the quantitative connections of parameters in the models for static recrystallization (SRX), meta-dynamic recrystallization (MDRX), and mean flow stress (MFS) were established with steel chemical compositions and deformation conditions. Through the machine learning (ML) approach, softening kinetics and rolling forces can be more accurately predicted than traditional models. Also, the recrystallization behavior and evolution of austenite grain size during hot rolling were analyzed by using the proposed ML models, which are consistent with experimental results.

Influence of 40% Cold Working and Annealing on Precipitation in AISI 316L Austenitic Stainless Steel.

Intergranular corrosion is one of the most important processes affecting the behaviour of austenitic stainless steels. Factors such as steel chemical composition, the degree of prior deformation and the exposure temperature affect the degree of sensitisation. AISI 316L (0% CW) steel was annealed at 650 °C for 5, 10, 30, 100, 300 and 1000 h to analyse the influence of isothermal annealing on the precipitation of secondary phases. AISI 316L steel after 40% cold working and subsequent annealing at 650 °C for 1, 1.5, 2, 5 and 10 h was investigated. Time–temperature sensitisation (TTS) diagrams were created based on corrosion test (ASTM A 262, practice A) results. In the case of AISI 316L (0% CW), M23C6, chi and sigma phases precipitated at grain boundaries, and the Laves phase was mainly inside of the grains. In the case of AISI 316L (40% CW), sigma, chi, Laves and M23C6 were identified and precipitated mainly along the grain boundaries as well as on the shear bands within different annealing times. It was confirmed that the increase in the annealing time caused an increase in the amounts of secondary phases. Secondary phases in the equilibrium state were calculated using Thermo-Calc software.

Multiscale modelling in nuclear ferritic steels: From nano-sized defects to embrittlement

Radiation-induced embrittlement of nuclear steels is one of the main limiting factors for safe long-term operation of nuclear power plants. In support of accurate and safe reactor pressure vessel (RPV) lifetime assessments, we developed a physics-based model that predicts RPV steel hardening and subsequent embrittlement as a consequence of the formation of nano-sized clusters of minor alloying elements. This model is shown to provide reliable assessments of embrittlement for a very wide range of materials, with higher accuracy than industrial correlations. The core of our model is a multiscale modelling tool that predicts the kinetics of solute clustering, given the steel chemical composition and its irradiation conditions. It is based on the observation that the formation of solute clusters ensues from atomic transport driven by radiation-induced mechanisms, differently from classical nucleation-and-growth theories. We then show that the predicted information about solute clustering can be translated into a reliable estimate for radiation-induced embrittlement, via standard hardening laws based on the dispersed barrier model. We demonstrate the validity of our approach by applying it to hundreds of nuclear reactors vessels from all over the world.

DEVELOPMENT AND IMPLEMENTATION OF A NEW METHOD FOR MODELING PHASE-STRUCTURAL TRANSFORMATIONS DURING COOLING OF ALLOY STEELS

Formulation of the problem. Modern research on the phase transformations modeling in low-alloy steels allow solving the problem of phase transformations quantitative determination for a given chemical composition of steel and different cooling rates. However, the possibilities of available universal software products for the complex alloy steels analysis are limited. The impossibility for users to integrate their own subroutines according to the phase transformation diagrams is their main disadvantage. Purpose of research. Modeling phase-structural transformations during cooling of complex-alloy steels taking into account the formation of all structural components, in particular residual austenite. To research, steels 25Cr2Mo1V and 38CrNi3MoV and existing analytical models were used, which were adapted to carry out the relevant calculations. Results. A new method for modeling phase-structural transformations during cooling of alloy steels is developed. Structural diagrams depending on the rate of continuous cooling are constructed for the investigated steels. For the first time, the amount of residual austenite is taken into account according to the developed method. Under developed method thermokinetic diagrams of investigated steels austenite transformation are constructed. According to the diagrams, the decay of austenite steel 38CrNi3MoV begins at lower temperatures compared to steel 25Cr2Mo1V. Steel 25Cr2Mo1V, with continuous cooling at a rate of 1.0 °C/s (conditions close to natural air cooling), consists of 18 % ferrite, 1 % pearlite, 80 % bainite and 1 % residual austenite. Steel 38CrNi3MoV cooled at a rate of 1,0 °C/s consists of 2 % ferrite, 47,5 % bainite, 50 % martensite and 0,5 % residual austenite. It is shown that the calculated data correlate well with practical results at the conditions of natural air cooling.

MODELING OF PHASE TRANSFORMATIONS DURING COOLING OF ALLOY STEELS

Modern studies on the modeling of phase transformations in low-alloy steels to a certain extent allow solving the problem of quantitative determination of phase transformations for a given chemical composition of steel and different cooling rates. However, the capabilities of the available universal software products for the analysis of complexly alloyed steels are currently very limited. To conduct research, steels 25Cr2Mo1V and 38CrNi3MoV and existing analytical models were used, which were adapted to carry out the corresponding calculations. Structural diagrams are plotted for the steels under study depending on the rate of continuous cooling. The amount of residual austenite was taken into account by the developed method for the first time. Steel 25Cr2Mo1V, with continuous cooling at a rate of 1.0 °C/s (conditions close to natural air cooling), consists of 18 % ferrite, 1 % pearlite, 80 % bainite and 1 % residual austenite. Steel 38CrNi3MoV cooled at a rate of 1.0 °C/s consists of 2 % ferrite, 47.5 % bainite, 50 % martensite and 0.5 % retained austenite. It is shown that for the conditions of natural air cooling, the calculated data correlate well with practical results.

APPLICATION OF EXPERIMENTAL PLANNING METHODS IN EVALUATION OF СТ3ГПС STEEL QUALITY ASSESSMENT

Introduction. Low-carbon low-alloy steels are widely used in construction. Therefore, despite the existence of a significant number of methods and ways to assess their quality criteria, the task of operational forecasting of these criteria is urgent. Difficulties in predicting the quality criteria of metal products from steels lie in the complexity of the technology of their production. If the parameters of the technology deviate from the normative documents, the properties of the material can differ significantly. In this regard, it is proposed to apply the method of experimental planning to estimate the tensile strength of low-carbon steel. Materials and methods. Samples of steel of ordinary quality Ст3Гпс made of a circle with a diameter of 24 mm were studied. The chemical composition of steel and its strength indicators varied within the normative documents in accordance with ГОСТ 380 and ДСТУ 2651. In the state of factory supply, the steel structure was ferritic-pearlitic. The content of the pearlite component, depending on the amount of carbon in the steel ranged from 11,2 to 17,6 %, the remaining fraction fell to ferrite. The results of the experiment. At the first stage of research the analysis of influence of each chemical element of steel on limit of its durability was carried out. To this end, with the help of the program "Expert", implemented on a computer, obtained one-factor models of strength forecast. In the second stage of research, the number of rows was reduced from 32 to 16 by implementing the matrix of experimental planning using the technique of small replicas. This approach significantly reduces the cost of experiments. The obtained multifactor (X1…X5) model for predicting the strength limit of steel St3Gps is adequate according to Fisher's and Cochren's criteria. According to Fisher's criterion, the coefficient of convergence of the results was 1,029 with a critical value of 2,400. The model is also adequate according to the Cochren test of 0,335 with a critical value of 0,547. At the third stage of research, based on the results of the analysis of the coefficients of the multiparameter model, histograms of complex assessment of the influence of chemical composition elements on the strength of steel are constructed. Conclusions. An adequate model for predicting its strength and histograms of the effect of its chemical composition on Ст3Гпс Steel was obtained. It makes sense to use the obtained results for the operational forecast of the strength of low-carbon steels in the state of factory delivery.

Corrosion resistance of welded tubing of L80 strength group of different chemical composition

In previous publications, it was shown that the use of low-carbon steels with bainite hardenability alloyed with chromium, molybdenum and other carbonitride-forming elements is promising for the production of cold-resistant and SCC (sulfide stress corrosion cracking)-resistant electricwelded tubing (tubing). Tubing is often operated in CO2-containing corrosive environments, therefore, determining the steel resistance to this type of corrosion is an urgent task. It is known that the addition of chromium to steel increases not only its hardenability, but also its resistance to CO2 corrosion. Influence of other alloying elements is not obvious. For the laboratory experiment, nine variants of the chemical composition of steels for the production of welded tubing were developed. The rolled test steels were investigated. Results of the studies of corrosion resistance of these steels are shown and compared. The authors made an assessment of influence of the main alloying elements on resistance to CO2 corrosion. The steels with different contents of Cr, Mo, V, Mn, Zr were studied for resistance CO2 corrosion at different temperatures. It has been established that the steel chemical composition and the test conditions determine the composition of CO2 corrosion products, affect the process of formation and growth of corrosion products, thereby affecting corrosion resistance. Decrease in the corrosion rate of chromium-alloyed steels can be associated with the protective properties of the corrosion products formed during testing. Laboratory corrosion tests for resistance to CO2 corrosion at an elevated temperature of 65 °C and subsequent studies of the formed corrosion products revealed a positive effect of chromium and molybdenum on the rate of general corrosion by mechanism of formation of dense corrosion products that perform a protective function.

Особливості формування неоднорідних структур у вуглецевих сталях

Obtaining a homogeneous structure and uniform-phase distribution is critical to a high set of mechanical and operational properties of rolled metal. However, in practice it is not always possible to create metal products with the specified characteristics. In order to determine the morphological features of the structure of rolled carbon steel, a comparative study of carbon steel samples with a carbon content of 0.49 % C and 0.2 % C selected from hot-rolled billets was carried out. The billets of each group were produced under the conditions of the same enterprise, with close temperature-time modes of deformation processing. The main difference was in manufacturing processes of the output continuous cast steel billets. This research shows that with identical normalized chemical composition of steel and the same thermomechanical treatment, the formation of the morphological structure features of hot-rolled steel occurs in a different way. Therefore, we can assume that the liquation, the diffusive mobility of elements is particularly influenced by the content of impurity elements and gases in steel, which leads to a different type of structures in the finished rolled metal. At the same time, these differences are observed in carbon steels with different carbon content. A sample of non-vacuumed OC grade axle steel (0.49 % C) from converter steelmaking has a more homogeneous structure without local areas of pearlite or ferrite accumulation. It was shown that the formation of ferrite rim in the microsegregation areas occurs not only in manganous sulfides, but also arises on the background of the smallest oxide inclusions. There is significant structural heterogeneity in the samples of electric steel, despite the lower sulfur content and gassiness of steel; at the same time, a dense perlite layer is formed around the sulfides. There is also a difference in steel grade 20 (0.2 % C) of different manufacturing processes. The structure is more homogeneous in qualitatively deoxidized vacuum degassed steel; no local areas with different dimensional characteristics were detected. The size of the structural elements is much larger and the structure has mostly large sections of the Widmanstatten ferrite. Since a large number of non-metallic inclusions and gassiness of steel is not a positive factor for providing a high set of properties of metal products, the modes of thermomechanical treatment used today require adjustments depending on the characteristics of steel melting. Keywords: microstructural heterogeneity, ferritic-pearlitic banding, mechanical properties, manganous sulfides.

Effect of Steel Hardness and Composition on the Boundary Lubricating Behavior of Low-Viscosity PAO Formulated with Dodecanoic Acid and Ionic Liquid Additives.

Two ionic liquids, tributylmethylphosphonium dimethylphosphate (PP) and 1-butyl-1-methylpyrrolidinium tris(pentafluoroethyl)trifluorophosphate (BMP), as lubricant additives in polyalphaolefin (PAO8) were studied under boundary lubricating conditions on two types of steel (AISI 52100 bearing steel and AISI 316L stainless steel). The tribological behavior of these ILs was compared with dodecanoic acid, a well-known organic friction modifier. This study employs a ball-on-disk tribometer with an alumina ball as a counterpart. A range of advanced analytical tools are used to analyze the tribofilms, including scanning electron microscopy equipped with a focused ion beam, scanning transmission electron microscopy equipped with X-ray energy-dispersive spectroscopy, and X-ray photoelectron spectroscopy. A quartz crystal microbalance with dissipation was used to study the surface adsorption of the additives on iron- and stainless steel-coated sensors to reveal the adsorption kinetics, adsorbed layer mass, and bonding strength of the adsorbed layer on the metallic surfaces. The most important factors controlling friction and wear are the thickness and viscoelastic properties of the adsorbed layer, the thickness and chemical composition of the tribofilm, and the hardness and chemical composition of steel. Among all additives studied, BMP on stainless steel gives a strongly adsorbed layer and a durable tribofilm, resulting in low friction and excellent antiwear properties.