Experimental Study on the Transition between Static and Kinetic Frictions of Steel/Shale Pairs

<div>Average friction coefficient <svg height="9.39034pt" id="M53" style="vertical-align:-3.42943pt" version="1.1" viewbox="-0.0498162 -5.96091 7.34167 9.39034" width="7.34167pt" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"><g transform="matrix(.013,0,0,-0.013,0,0)"><path d="M538 96L524 119C492 88 454 63 446 63C439 63 434 70 440 101C463 223 491 341 518 448H508L433 422L401 276C355 192 240 56 188 56C163 56 154 89 163 133C184 233 207 338 235 443L230 448L152 424L58 17C40 -60 23 -143 23 -185C23 -241 42 -261 63 -261C92 -261 117 -241 125 -227L124 -221C109 -209 89 -165 89 -103C89 -55 96 -13 105 26H107C121 -3 134 -12 151 -12C172 -12 194 -5 221 16C279 61 330 124 384 194H386C381 159 377 141 368 105C343 3 363 -12 383 -12C416 -12 486 35 538 96Z"></path></g></svg> versus displacement <i>U</i> and the estimated <i>D</i><sub>c</sub><span class="nowrap"><svg height="12.7178pt" id="M54" style="vertical-align:-3.42947pt" version="1.1" viewbox="-0.0498162 -9.28833 89.5313 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609 64 710L45 686C145 604 203 442 203 270S147 -63 45 -147L64 -170C213 -68 275 89 275 270Z"></path></g></svg>.</span> (a) Unlubricated. (b) Lubricated.</div>

Shock and Vibration

fig8

Figure 8

Figure 8: Experimental Study on the Transition between Static and Kinetic Frictions of Steel/Shale Pairs 