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Volume 14, Issue 12 (December 2025)

Thermal Analysis on ABS & HDPE Materials of Bonding Strength by Ultrasonic Welding

DOI : https://doi.org/10.5281/zenodo.18136497
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Kanusu Ramachandra Rao, Balaga Siva Srinivas, Pagoti Damodara Rao, Potnuru Suresh, 2026, Thermal Analysis on ABS & HDPE Materials of Bonding Strength by Ultrasonic Welding, INTERNATIONAL JOURNAL OF ENGINEERING RESEARCH & TECHNOLOGY (IJERT) Volume 14, Issue 12 , December – 2025, 10.17577/IJERTV14IS120704

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Thermal Analysis on ABS & HDPE Materials of Bonding Strength by Ultrasonic Welding

Kanusu Ramachandra Rao, Balaga Siva Srinivas, Pagoti Damodara Rao, Potnuru Suresh

Lecturer in Aditya Institute of Technology & Management, Tekkali,

Abstract – Ultrasonic plastic welding has received significant attention in the past few years, and has become more reliable and suitable for a wide range of applications. In recent years, technique has been extensively used due to the advent of component miniaturization and improvements in producing lightweight components. There are a number of advantages for ultrasonic plastic welding, including greater efficiency and speed, longer tool life, higher accuracy and no filler or flux needed to be used. Thus the technique can be viewed as being environmentally friendly

In this work effect of various parameters on weld strength have been studied. Welding of 0.5 mm thickness Acryl nitride Butadiene-Styrene (ABS) and High Density Polyethylene (HDPE).plates were successfully welded by 20 kHz ultrasonic welding system. This experiment was carried to find out the optimum parameter for maximum strength. In order to determine critical states of the welding parameters, analysis of variances has applied while optimization of the parameters affecting the joint strength has achieved with centre composite method of the Response Surface Methodology. This study involves modeling of experimental data of joint strength of ABS & HDPE material for ultrasonic welding on welding parameters (welding pressure, welding time, and amplitude. Results are compared with Analytical values.

Keywords – Ultrasonic Welding, Thermoplastic Material, Process Parameters, JOINT Strength, Full Factorial Method, ANOVA, Response Surface.

  1. INTRODUCTION
    1. HISTORY

      The use of ultrasonic in some form may be found in nearly every industry today whether it is high powered applications such as Ultrasonic welding or low powered applications such as imaging, non-destructive testing and cleaning. Ultrasonic pertains to acoustic frequencies above the audible range of the human ear, which is approximately 20,000 cycles per second. Ultrasonic Welding (USW) may be comparable to other attachment processes that involve fusion through such methods of application of heat via flame or hot tool, electrical current, electrical arc or adhesives. Many of these processes involve surface preparation and processes additives such as fluxing agents and filler materials. Ultrasonic welding has existed since the early 1950s. However, the first patent regarding an ultrasonic welding machine was not granted until the 1960s because it was not believed by the patent supervisor that there existed a machine that could make a metallurgical bond without the use of heat or filler materials. Early machines where, inefficient, expensive and quite large, while todays machines are much more efficient This increase in efficiency may be manly contributed to a change in the methods of creating ultrasonic vibrations. Early converters transformed electrical energy to mechanical vibrations with the use of ferromagnetic materials. A current was induced in this magneto astrictive material, which created a periodic alternating magnetic field, therefore causing a dimensional change in the material. Today however, ultrasonic welders produced oscillations through piezoelectric ceramics. Re-alignment of dipoles inside the elementary cells of the piezoelectric ceramic causes an incremental change in volume In the present research, an experimental investigation of Ultrasonic welding of dissimilar plastics between ABS & PC has been carried out. Response surface methodology (RSM) is employed to develop mathematical relationships between the welding process parameters namely Amplitude, Pressure and Weld time and the output variable Welding Strength. The developed mathematical model is tested by analysis-of-variance (ANOVA) method to check its competence. This mathematical model is useful for predicting the weld strength as well as for selecting the optimum process parameters. The influence of process parameters on weld strength are discussed based on the main effect and interaction plots

  2. EXPERIMENT
    1. EXPERIMENTAL SETUP

      The welding was carried out using a conventional ultrasonic plastic welding machine (2,500 W, 20 kHz). The specification of the machine is shown in the table 1. The actual experimental setup is as shown in Fig1 with the data acquisition system. A horn made of titanium alloy was used for this study and an anvil made of steel with serrations at the top surface. The parameters that can be varied in this setup are the weld pressure, weld time, and the amplitude of vibration. These factors are selected as the variables for this study. The area of horn that comes into contact has serrations similar to the top surface of the anvil for gripping the work piece well. The specimen (0.5 mm ABS &HDPE sheet) was prepared as per standard for testing shear strengths of the joint by tensile loading. A universal testing machine was used to determine the weld strengths. The temperature at the interface of the specimen was monitored in real time using a data acquisition system. The data acquisition system includes sensors (thermocouple), a terminal block, DAQ card, and analyzing software. An SWG 36 AlumalCromal (type K) thermocouple is used in this study which can measure temperatures from -180°C to +1,300°C. It has a high accuracy of 1.5°C on each side from -40°C to +375°C

      Table 1: ultrasonic machine specifications

      S.NO DESCRIPTION VALUES
      1 INPUT POWDER 2500W
      2 OUTPUT FREQUENCY 20KHZ
      3 MAXIMUM AMPLITUDE 50m
      4 MAXIMUM FORCE 300N
      5 STROKE LENGTH 100mm

      Fig 1 experimental setup

      2.2. Welding Parameters

      There are mainly two types of factor that affect any process one is the controlled and another is uncontrolled one. Here in the USW, the controlled factors are welding time, welding pressure, input power, frequency, amplitude etc. The uncontrolled factors are that factors which cant be controlled during process. In this paper, the uncontrolled factors were neglected and controlled factors were selected for study. It has noted that most affecting parameters were welding time, welding pressure and amplitude of sonotrode. Here all three factors were considered. Each of the factors with three levels has taken as shown in table 2.

      Table 2: Factors and levels for the experiments

      Factors Level 1 Level 2 Level 3
      Pressure (bar) 1.5 2 2.5
      Amplitude (µm) 40 45 50
      Welding Time (s) 2 2.25 2.50

      2.3 Methodology

      In this research work the specimen has prepared according to ASTM standard . The specimen selected for the experiment is ABS material having (80 × 50 mm) and 0.5 mm thickness. Total 9 run have identified Values applying design of experiment with 3 input parameters and 3 levels. Here the joint strength has mesured by universal testing machine as one output parameter. During the tensile testing, ductile fracture has observed at weld interface for most of the welded samples. Analysis of variance (ANOVA) has used to identify significant effect of parameters and regression analysis have to follow to optimize parameter values for maximum joint strength.

  3. Result and discussion

    Identified 29 runs to experiment, using centre composite technique of response surface method. Designs of experiment have performed and corresponding joint strength have recorded. The data acquisition system includes sensors (thermocouple), a terminal block, DAQ card, and analyzing software. An SWG 36 AlumalCromal (type K) thermocouple is used in this study which can measure temperatures. Experimental results are shown in below Table 3.

    Table 3: Experimental results

    Ex.

    No.

    		 Welding Pressure (bar)

    A

    		 Amplitude (µm)

    C

    		 Welding Time (sec)

    B

    		 Response
    Interface Temperature (oC) Joint Strength (MPa)
    Trials Average Trials Average
    1 2 3 1 2 3
    1 1.5 40 2 105 112 106 107.66 1.58 1.80 1.87 1.75
    2 1.5 45 2.25 102 106 110 106 2.09 2.31 2.22 2.21
    3 1.5 50 2.50 85 98 102 95 3.32 2.60 2.24 2.72
    4 2 40 2. 115 106 112 111 2.09 2.45 2.09 2.18
    5 2 45 2.25 102 116 108 108.66 4.26 3.32 2.31 3.29
    6 2 50 2.50 103 105 110 106 1.44 1.95 2.24 1.87
    7 2.5 40 2 90 95 105 96.66 3.65 3.33 2.60 2.72
    8 2.5 45 2.25 117 110 102 109.66 3.22 2.42 1.92 1.87
    9 2.5 50 2.50 125 115 122 120.66 1.44 1.80 1.58 1.60

    Welding strength was calculated by using basic physics.

    Final Equation: Joint Strength = +5.39 +0.12 * A +0.088 * B +0.39 * C -0.21 * A2 -0.62 * B2 -0.073 * C2 +0.024 * A* B +0.14 * A * C -0.39 * B * C

    By using this above equation joint strength is calculated at different parameters

    1. Joint strength = +5.39 +0.12 *(1.5) +0.088 *(2) +0.39 *(40) -0.21 * (1.5)2 -0.62 *(2) 2 -0.073 * (40)2 +0.024 * (1.5)* (2) +0.14 *

      (1.5) * (40) -0.39 * (2) * (40) = 1.75 MPa

    2. Joint Strength = +5.39 +0.12 * 1.5 +0.088 * 2.5 +0.39 * 45 -0.21 * (1.5)2 -0.62 * (2.5)2 -0.073 * (45)2 +0.024 * 1.5* 2.5 +0.14 * 1.5

      * 45 -0.39 * 2.5 * 45 =2.21 MPa

    3. Joint Strength = +5.39 +0.12 * 1.5 +0.088 * 2.50 +0.39 * 50 -0.21 * 1.52 -0.62 * 2.502 -0.073 * 502 +0.024 * 1.5* 2.50 +0.14 * 1.5 *

      50 -0.39 * 2.50 * 50 =2.72MPa

    4. Joint Strength = +5.39 +0.12 * 2 +0.088 * 2 +0.39 * 40 -0.21 * 22 -0.62 * 22 -0.073 * 402 +0.024 * 2* 2 +0.14 * 2 * 40 -0.39 * 2 *

      40 =2.18MPa

    5. Joint Strength = +5.39 +0.12 * 2 +0.088 * 2.25 +0.39 * 45 -0.21 * 22 -0.62 * 2.252 -0.073 * 452 +0.024 * 2* 2.25 +0.14 * 2 * 45 –

      0.39 * 2.25 * 45 =3.29MPa

    6. Joint Strength = +5.39 +0.12 * 2 +0.088 * 2.50 +0.39 * 50 -0.21 * 22 -0.62 * 2.502 -0.073 * 502 +0.024 * 2* 2.50 +0.14 * 2 * 50 –

      0.39 * 2.50 * 50 =1.87MPa

    7. Joint Strength = +5.39 +0.12 * 2.25 +0.088 * 2 +0.39 * 40 -0.21 * 2.252 -0.62 * 22 -0.073 * 402 +0.024 * 2.25* 2 +0.14 * 2.25 * 40

      -0.39 * 2 * 40 =2.72MPa

    8. Joint Strength = +5.39 +0.12 * 2.25 +0.088 * 2.25 +0.39 * 45 -0.21 * 2.252 -0.62 * 2.252 -0.073 * 452 +0.024 * 2.25* 2.25 +0.14 *

      2.25 * 45 -0.39 * 2.25 * 45 = 1.87MPa

    9. Joint Strength = +5.39 +0.12 * 2.5 +0.088 * 2.50 +0.39 * 50 -0.21 * 2.52 -0.62 * 2.502 -0.073 * 502 +0.024 * 2.5* 2.50 +0.14 * 2.5 *

    2.50 -0.39 * 2.50 * 50 =1.60MPa

    From the above graph is weld strength with respect to temperature in this graph weld strength is maximum at 3.29MPa at temperature 108.666oc

    1. Analysis of Variance (ANOVA) :

The purpose of the analysis of variance (ANOVA) is to investigate which parameters significantly affected the process. In order to perform ANOVA, the total sum of square, SST is calculated using following formula:

Where, C.F. = Correction Factor

yi = Response parameter (Welding Strength) of the i runs

N = Number of runs Value of N is considered 18 (9×2) as each specimen was tested two times. Also, correction factor is calculated using following formula: C.F. = T2/N

Where, T = Total of the response (Welding Strength)

Mean Square (Variance) which is produced by dividing Sum of Square by Degree of freedom of factors. F Value, which is the ratio produced by dividing the Mean Square for the Model by the Mean Square for Error

Below Table shows the result of Analysis of Variance.

Table 4: Analysis of Variance

Symbol Factors Degree of Freedom Sum of

Square

 Mean Square F Ratio %

Contributi on
A Amplitude 2 117.5022 58.751 95.304 32.32%
B Pressure 2 62.8435 31.422 50.971 17.28%
C Time 2 111.5897 55.795 90.508 30.69%
D Thickness 2 66.1028 33.051 53.615 18.18%
Error 9 5.548 0.616 1.53%
Total 17 363.5864 21.387 100.00%

From the ANOVA results it was observed that Amplitude and time are the most significant factors affecting the ultrasonic welding of ABS and HDPE. The percentage contribution for both Amplitude and time are 32.32% and 30.69% respectively. Thus, it can be concluded that Amplitude and time are the statistically significant parameter.

    1. ANALYSIS OF BONDING STRENGTH:
      1. EXPERIMENTATION AND DATA COLLECTION:

        The below table 4 the different parameters are taken with different levels in this process to weld the materials used in ultrasonic welding

        Table 5: parameters and their levels of experiment

        SYMBOLS PROCESS

        PARAMETERS

        		 LEVELS
        LOW MEDIUM HIGH
        V Voltage (Volt) 220 230 240
        I Current (amp) 10.4 10.8 11.6
        P Pressure (MPa) 1.5 2 2.5
      2. EXPERIMENTAL RESULTS:

        The below table 5 is consolidated design of experiment done by different parameters

        Table 6: Consolidated design of experiment table

        EXPERIMENT

        NO

        		 Voltage

        (v)

        		 Current

        (amp)

        		 Pressure

        (MPa)

        		 Strength

        (106N/m2)
        1 220 10.4 1.5 1.75
        2 220 10.8 2 2.21
        3 220 11.6 2.5 2.72
        4 230 10.4 1.5 2.18
        5 230 10.8 2 3.29
        6 230 11.6 2.5 1.87
        7 240 10.4 1.5 2.72
        8 240 10.8 2 1.87
        9 240 11.6 2.5 1.60

        In this work, the controllable factors taken are Voltage (V), Current (I) and pressure (P). Since they affect strength and welding operation and these factors are controllable in the ultrasonic welding process, they are considered as a controllable factor.

      3. Analysis of means and response graph for strength:

        The analysis of each controllable factor is studied and the main effect of the same is obtained in table. Main effect of each factor at individual level i.e. at low, medium and high level is equal to the mean of strength of all experiments with the factor at individual level.

        1. The main effect of voltage on strength at various levels calculated as follows

          L = (1.75+2.21+2.72)/3 =2.22 (106N/m2)

          M = (2.18+3.29+1.87)/3 =2.44 (106N/m2) H = (2.72+1.87+1.60)/3 =2.06 (106N/m2)

        2. The main effect of current on strength at various levels calculated as follows

          L = (1.75+2.18+2.72)/3 =2.21 (106N/m2)

          M = (2.21+3.29+1.87)/3 =2.45(106N/m2) H = (2.72+1.87+1.60)/3 = 2.06(106N/m2)

        3. The main effect of pr ure on strength at various levels calculated as follows

        L = (1.75+3.29+1.60)/3 = 2.21 (106N/m2)

        M = (2.21+1.87+2.72)/3 = 2.26(106N/m2) H = (2.72+2.18+1.87)/3 =2.25(106N/m2)

        Table 7: Responses for strength

        Symbols Controlled factors Strength(106N/m2)
        Low Medium High
        V Voltage 2.39 2.44 2.06
        I Current 2.21 2.45 2.43
        P Power 2.21 2.26 2.25

        The value obtained from the response table are plotted to visualize the effect of three parameters. From the means response graph observation finding are illustrated as follows-

        1. Level III for voltage (V2) =2.44(106N/m2) indicated as the optimum situation in terms of strength.
        2. Level II for current (I2) =2.45(106N/m2) indicated as the optimum situation in terms of strength.
        3. Level III for voltage (P2) =2.26(106N/m2) indicated as the optimum situation in terms of strength.

        Main effect plot for Strength

         

        Confirmation of experiment

        For maximum strength the combination of optimum parameters (V2, I2, P2).It means high voltage, medium current and high pressure. For this combination V2=230v, I2=10.8 amp and P2= 2 MPa, the strength is 3.29 (106N/m2)

      4. MODELLING OF PARAMETERS

        To generalize the result, the modeling of input parameters (Voltage, Current and Pressure) and output parameters (Strength) is done using REGRESSION MODELING and Mat lab software R2011b. Now the Formula of strength in terms of voltage, Current, and Pressure

        Strength = (Voltage) 0.5514* (Current) 0.1431* (Pressure) 1.5115

        Table 8: Experimental results & Result from Mathematical modeling

        Strength
        Experimental result Result from mathematical modeling
        1.75 2.86
        2.21 3.77
        3.22 4.30
        2.18 4.57
        3.29 5.37
        2.76 5.01
        2.72 3.81
        1.87 5.28
        1.60 2.67

        Comparison of result for maximum strength

        1. Strength = (220) 0.5514* (10.4) 0.1431* (1.5) 1.5115 = 2.86
        2. Strength = (220) 0.5514* (10.8) 0.1431* (2) 1.5115 =3.77
        3. Strength = (220) 0.5514* (11.6) 0.1431* (2.5) 1.5115 =4.30
        4. Strength = (230) 0.5514* (10.4) 0.1431* (1.5) 1.5115 =4.57
        5. Strength = (230) 0.5514* (10.8) 0.1431* (2) 1.5115 =5.37
        6. Strength = (230) 0.5514* (11.6) 0.1431* (2.5) 1.5115 =5.01
        7. Strength = (240) 0.5514* (10.4) 0.1431* (1.5) 1.5115 =3.81
        8. Strength = (240) 0.5514* (10.8) 0.1431* (2) 1.5115 =5.28
        9. Strength = (240) 0.5514* (11.6) 0.1431* (2.5) 1.5115 =2.67
          RESULTS Experimental result Result from mathematical modeling
          LEVEL V2I2P2 V2I2P2
          STRENGTH(106N/m2) 3.29 5.37

          Result from mathematical modeling

          From the graph is between experimental results and results from mathematical modeling from this results the weld strength is maximum at V2I2P2

          3.2.5. Welding Heat Input:

          Formula

          The below mathematical formula is used in mechanical engineering to calculate how much heat for welding. Q = (A x V x 60)/TS

          TS = (L/S) x60

          Substitute

          Q = (V x A x S)/L

          Where L=length in mm

          S=weld time in sec

          A-welding current in amps V-voltage in volts

          Q= joules/mm

          In the field of mechanical engineering, while working with heat transfer, sometimes it’s important to analyze welding heat to finish a particular job. The above formula & step by step calculation may be useful for users to understand how the values are being used in the formula to find the heat input, however, when it comes to online for quick calculations, this welding heat calculator helps the user to perform & verify such mechanical engineering heat transfer calculations as quick as possible.

          Table 9: heat input for welding results

          S.NO Voltage(volts) Current(amps) Weld time(sec) Heat

          input(joules/mm)
          1 220 10.4 2 193.734
          2 220 10.8 2.25 226.525
          3 220 11.6 2.50 270.332
          4 230 10.4 2 202.711
          5 230 10.8 2.25 236.822
          6 230 11.6 2.50 282.627
          7 240 10.4 2 211.525
          8 240 10.8 2.25 247.118
          9 240 11.6 2.50 294.665

          Calculation

          1. Q=(V x A x S)/L=(220*10.4*2)/2.36=193.734
          2. Q=(V x A x S)/L=(220*10.8*2.25)/2.36=226.525
          3. Q=(V x A x S)/L=(220*11.6*2.50)/2.36=270.332
          4. Q=(V x A x S)/L=(230*10.4*2)/2.36=202.711
          5. Q=(V x A x S)/L=(230*10.8*2.25)/2.36=236.822
          6. Q=(V x A x S)/L=(230*11.6*2.50)/2.36=282.627
          7. Q=(V x A x S)/L=(240*10.4*2)/2.36=211.525
          8. Q=(V x A x S)/L=(240*10.8*2.25)/2.36=247.118
          9. Q=(V x A x S)/L=(240*11.6*2.50)/2.36=294.66

          Graph between welding heat input and temperature

          From the above graph heat input in welding varies different temperature. From this study welding strength is maximum at 108.66oc and the heat input at this temperature is 236.822 j/mm

      5. Modeling of experimental data of joint strength

Fig 3.2.5(a) Response surface, Effect of pressure and weld time on weld strength

From the fig 3.2.5(a) shows the effect of pressure and weld time on weld strength by using the response surface methodology

Fig 3.2.5(b) Response surface, Effect of amplitude and pressure on weld strength

From the fig 3.2.5(b) shows the effect of pressure and amplitude on weld strength by using the response surface methodology

Fig 3.2.5(c) Response surface, Effect of amplitude and weld time on weld strength

From the fig 3.2.5(C) shows the effect of amplitude and weld time on weld strength by using the response surface methodology

  1. DISCUSSIONS

    The specimens used in this work were made of Acryl nitride Butadiene-Styrene (ABS) and High Density Polyethylene (HDPE). The experiment is done at three levels i.e., level 1, level 2 and level 3 respectively. The experimental factors are pressure, amplitude and weld time. This experiment is carried on at 3 levels where each factor is applied to other factors in 3 different ways. The above table shows the results obtained from the experiment. In this investigation weld at 2 bar weld pressure, 2.50 sec weld time and amplitude 45 welding pressure is maximum 3.29(10^6N/m^2).while compare to others weld strengths hence these parameters are preferable for this process and also by using REGRESSION MODELING and Mat lab software R2011b we can proved weld strength at V2I2P2 is prefer for welding process and also response surface methodology also used to find the different parameters are effecting on weld strength In this investigation calculating the how much heat for welding occurred in these process with respect to temperature.

  2. CONCLUSION
  • Experimental and analytical thermal analysis on ultrasonic welding process parameter improvement have been performed on Acryl nitride Butadiene-Styrene (ABS) and High Density Polyethylene (HDPE)
  • In this study, RESPONSE SURFACE METHODOLOGY (RSM) has revalidated to predict the most weld strength of welds created by USW
  • From the outcomes, it was discovered that the welding strength mainly depends on value of amplitude and then on amount of weld pressure also weld time
  • Beyond 2 bar, the weld strength again start decreasing for constant value of amplitude and weld time. This is because increase in pressure reduces the relative motion between surfaces and that leads to reduced area of contact and so reduced strength.
  • Optimized weld strength has observed to be maximum 3.29 MPa at 2 bar weld pressure; 2.50 sec weld time and amplitude of 45 µm. Results of present investigation have been valuable to choose ideal welding condition, at which the most extreme weld quality can accomplish to enhance weld capacity of nonmetallic material and rate of creation.
  • From the a above results we observed that welding strength is is maximum at temperature 108.660c and heat is generated at that welding point is 236.822 j/mm

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