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选择用于测试耐磨性的试样的硼化层的厚度为0.3—0.4，为了减少脆性，增加硼化层的厚度，751分之一的样品应在1000℃ 的中性气氛中进行扩散退火（均匀）四小时。这就使得一个单相硼化层的厚度大约是（0.7-0.8毫米）。
五分之一批样品进行碳氮共渗（浸泡在800℃的淬火油中5小时）。这一过程后的碳氮共渗层的油淬后压强为8300 MPa，硬度厚度0.8-1毫米。
破碎机在测试标本时的工作参数同那些在正常生产中粉碎石英砂时的工作参数是相似的。转子速度为80米/秒；破碎机产量为50公斤/小时；破碎时间为30分钟。
涂层的耐磨性一般是相对而言的并不是绝对的条款。因此，耐磨性是指对材料的磨损量的比值，用于在相同的时间相同的条件下控制和测试样本：= AGc/&G m（这里的分别是控制和测试材料的磨损量）。提供控制条件的试样是由45钢制成的。
这些标本的耐磨性重测试之前和之后在天平的准确性相差为±2mg。我们可以看出, 当破碎机破碎石英砂时，用硼酸处理且对其进行扩散退火处理后的标本具有最高的耐磨性。在相同的试验条件下其耐磨性是高于45钢的8倍。碳氮共渗试样的耐磨性高于45钢是基于两个因素。
磨损模式的分析表明，在一个快速的空气磨料流的作用下严重磨损发生在主要面角，其次是边缘磨损，最后是其他工作面。这种现象是很难定义的尤其是当在测试脆硼涂层时（没有热处理），由于在叶片的边缘和角的局部应力过度和涂层的脆性很大的原因。
硼化层退火脆性的扩撒，从而大大降低了局部脆性使得耐磨性增加。破碎机的引导面操作30分钟后（承担在粉碎磨的主要负载）硼化标本在中性气氛退火有一个0.02-0.03 mm穿孔，而角（具有2的圆角半径）有一个0.6 mm的磨损。60分钟后对其角端面的磨损进行额外的测试，其测试值分别是0.08和1.1毫米。在这一阶段的试样基体金属是可见的。然而，这批标本的耐磨性仍超过45钢的4- 5倍。
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The material is packed to 700 cc volume using a vibrating table. This is the volumetric weight of the material to be used for grinding tests. For the first grinding cycle, the mill is started with an arbitrarily chosen number of mill revolutions. At the end of each grinding cycle, the entire product is discharged from the mill and is screened on a test sieve size (Pi). Standard choice for Pi is 106 μ. The oversize fraction is returned to the mill for the second run together with fresh feed to make up the original weight corresponding to 700 cc. The weight of product per unit of mill revolution, called the ore grindability of the cycle, is then calculated and is used to estimate the number of revolutions required for the second run to be equivalent to a circulating load of 250%. The process is continued until a constant value of the grindability is achieved, which is the equilibrium condition. This equilibrium condition may be reached in 6–12 grinding cycles. After reaching equilibrium, the grindabilities for the last three cycles are averaged. The average value is taken as the standard Bond grindability (Gbg).
The products of the total final three cycles are combined to form the equilibrium rest product. Sieve analysis is carried out on the material and the results are plotted, to find the 80% passing size of the product (P80). The Bond work index values (Wi) are calculated from the Eq. (2) .
(2)
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3. Experiments
Firstly, standard Bond grindability tests were performed for three limestone samples. From the result of tests, Bond work index values were calculated 4.44, 10.10 and 13.53 kW h/t, respectively. Then, 1 kg sample of six mono-size fractions (−6.7 + 4.75, −4.75 + 2.8, −2.8 + 1.7, −1.7 + 1.18, −1.18 + 0.600, −0.600 + 0.355 mm) were prepared by screens for determination of the t-family curves. The laboratory impact crusher (Fig. 4), used in the experiments, works with driven by a 1.1 kW motor, rotating at 2840 rpm, carry three rows of hammers. Each sample was taken out of the laboratory impact crusher, and then samples were sieved for product size analysis.